Update README.md

README.md

@@ -20,10 +20,10 @@ THIS IS EXPERIMENTAL SOFTWARE. Use it for educational purposes only.
 
 ### License
 
-The source code is distributed under the `MIT software license`, see the accompanying file LICENSE or visit http://www.opensource.org/licenses/mit-license.php.
+The source code is distributed under the `MIT software license`, see the accompanying [LICENSE](LICENSE) file or visit http://www.opensource.org/licenses/mit-license.php.
 
-This product includes software developed by the OpenSSL Project and Denis Grinyuk (https://github.com/Arvur/OpenSSL-Delphi), and some  
-cryptographic functions inspirated in code written by Ladar Levison and Marco Ferrante.  
+This product includes software developed by the OpenSSL Project and Denis Grinyuk (https://github.com/Arvur/OpenSSL-Delphi) and some  
+cryptographic functions inspirated in code written by Ladar Levison and Marco Ferrante.
 
 Go to https://www.pascalcoin.org to find out more.
 
@@ -46,689 +46,3 @@ Send donations to `16K3HCZRhFUtM8GdWRcfKeaa6KsuyxZaYk`
 #### Pascal
 
 Send donations to account: `0-10`
-
-## History:  
-
-### Current Build (Pending release date)
-- Upgrade to Protocol 5 (Hard fork)
-- Implementation of PIP-0030 -> https://github.com/PascalCoin/PascalCoin/blob/master/PIP/PIP-0030.md
-- Implementation of PIP-0029 -> https://github.com/PascalCoin/PascalCoin/blob/master/PIP/PIP-0029.md
-- New digest hash value for OP_DATA ( PIP-0016 ) on Protocol 5
-TODO  
-- TODO: RPC calls for PIP-0029
-- TODO Implement Seal calculation
-- TODO: RPC calls for PIP-0030
-- TODO: RPC calls for PIP-0016
-- TODO: Save data for GUID on OPDATA operation and use GUID for calcs
-
-### Build 4.0.3.1 - 2019-04-12
-- Fixed core bug #182 in RPC calls
-
-### Build 4.0.3 - 2019-04-10
-- Improvements:
-  - Up to +1600 operations per second using a domestic computer (4 CPU)
-  - Download and check new Safebox in less than 5 minutes
-- TESTNET:
-  - Added functions to automatically receive new accounts for new installed fresh nodes
-- Major refactoring: 
-  - Change TRawBytes from "AnsiString" to "TBytes" type
-  - Do not use AnsiString type for simple string types, use String instead
-  - Usage of TList<T> type
-  - Allow compilation using Delphi 10.2 and multidevice (Firemonkey)
-- Core features
-  - Added CryptoLib4Pascal library that will allow to replace OpenSSL in a future for a Pascal pure native cryptographic suite (for testing purposes at this moment, not actived by default)
-  - Important log reduction
-  - Adding multithreading validation
-    - Multithreading validating Signatures
-    - Multithreading validating Blocks headers (TOperationBlock)
-- Fixed core bugs:
-  - Miner bug after loading blocks on start-up if last saved block was a checkpoint block
-- Gui-Classic
-  - Multithread on User Accounts to avoid freeze when updating data
-  - Fixed Minor bugs (See GitHub commits since 2019-01-08)  
-
-### Build 4.0.2 - 2019-01-08
-- Improvement speed (high performance): checking valid signature only once if operation is on mempool and was verified previously
-- Improved operations/blocks propagation
-- Fixed a decompression bug caused by FreePascal "paszlib" package bug on version 3.0.4 -> https://bugs.freepascal.org/view.php?id=34422
-- Allow download new safebox (instead of download pending blocks) when difference > TNode.MinFutureBlocksToDownloadNewSafebox
-  - 7 days by default for Production, 1 for Testnet
-  - Disabled by default on Daemon, configure on INI file with MINPENDINGBLOCKSTODOWNLOADCHECKPOINT
-  - Enabled by default on GUI, can configure it
-  - Will not delete current blockchain, but will not download pending blocks between last block saved and current network checkpoint block
-- Allow only connections using Net protocol >= 9  (Introduced on Build 4.0.1)
-- Fill automatic params at "buyaccount" RPC call: Will set 'price' and 'seller_account' values to current safebox values if not provided
-- Improved memory usage on mempool operations (TPCOperationsStorage)
-- Important logs reduction to store only logs that are important
-- Fixed minor bugs and minor improvements (See GitHub commits since 2018-10-31)
-
-### Build 4.0.1 - 2018-10-31
-- Fixed a critical "Access violation" at "Fast Block Propagation" process
-- Fixed a critical "Access violation" at "Get blockchain operations" process
-- Fixed a memory leak at "Get Block operations"
-- Updated Net protocol available to 9 (8 was introduced at build 4.0.0)
-
-### Build 4.0.0 - 2018-10-26
-- MANDATORY UPGRADE - HARD FORK ACTIVATION WILL OCCUR ON BLOCK 260000
-  - PIP - 0009: RandomHash
-    - RandomHash is a new hash algo created by Herman Schoenfeld, see https://github.com/PascalCoin/PascalCoin/blob/master/PIP/PIP-0009.md 
-  - PIP - 0015: Fast Block Propagation
-  - PIP - 0016: Layer-2 protocol support 
-  - Critical bug fix: New digest hash for signature verifications
-  - Limit blockchain to allow max only one 0-fee operation by signer per block (prior was limited by network, not by core)  
-  - Added OrderedAccountKeysList that allows an indexed search of public keys in the safebox with mem optimization
-  - Improved net protections
-- JSON-RPC changes:
-  - New protection for "open ports" server: When a server has whitelist to ALL IP's access to JSON-RPC calls, all calls that use the wallet keys are protected to avoid hacking
-    - Added param "RPC_ALLOWUSEPRIVATEKEYS" on pascalcoin_daemon.ini file
-  - New params for "findaccounts":
-    - "exact" (Boolean, True by default): Only apply when "name" param has value, will return exact match or not
-    - "listed" (Boolean, False by default): Will return only listed for sale accounts
-    - "min_balance","max_balance" (PASCURRENCY): Filter by balance
-	- "enc_pubkey" or "b58_pubkey": If provided will search accounts with this pubkey. In this case the "start" param value is the position of indexed public keys list instead of accounts numbers
-  - New return param in "Multioperation Object"
-    - "digest" (HEXASTRING): Returns the digest value that must be signed
-  - New param for "multioperationsignoffline"
-    - "protocol" (Integer): Must provide protocol version. By default will use build protocol constant CT_BUILD_PROTOCOL
-  - New param for "signsendto"
-    - "protocol" (Integer): Must provide protocol version. By default will use build protocol constant CT_BUILD_PROTOCOL
-  - New param for "signchangekey"
-    - "protocol" (Integer): Must provide protocol version. By default will use build protocol constant CT_BUILD_PROTOCOL
-  - New param for "signlistaccountforsale"
-    - "protocol" (Integer): Must provide protocol version. By default will use build protocol constant CT_BUILD_PROTOCOL
-  - New param for "signdelistaccountforsale"
-    - "protocol" (Integer): Must provide protocol version. By default will use build protocol constant CT_BUILD_PROTOCOL
-  - New param for "signchangeaccountinfo"
-    - "protocol" (Integer): Must provide protocol version. By default will use build protocol constant CT_BUILD_PROTOCOL
-  - New param for "signbuyaccount"
-    - "protocol" (Integer): Must provide protocol version. By default will use build protocol constant CT_BUILD_PROTOCOL
-  - Account Object change:
-    - Changed return value of "price". Previously was returned without decimals in native value (inconsistency bug), now will be returned as a PASCURRENCY (with 4 decimals)
-- Bug fixed: DoProcess_GetAccount_Request request type=1 (single account) didn't returned only 1
-- Bug fixed: Invalid "lastBlockCache" value when found and orphan block that causes invalid propagation until a new block is found. Fixed.
-- Bug fixed: "Access violation" on "getpendings" JSON-RPC call when pendings count>0
-- Net protocol upgraded to "8" in order to accept new network p2p calls:
-  - "Fast block propagation" : NetOp 0x0012 for PIP-0015 
-  - "Get blockchain operations": NetOp 0x0013 for PIP-0015
-  - "Get Public key accounts": NetOp 0x0032
-
-### Build 3.0.1 - 2018-05-07
-- Deprecated use of OpenSSL v1.0 versions. Only allowed OpenSSL v1.1 versions
-- JSON-RPC Added param "openssl" on "nodestatus" call. Will return OpenSSL library version as described in OpenSSL_version_num ( https://www.openssl.org/docs/man1.1.0/crypto/OPENSSL_VERSION_NUMBER.html )
-
-### Build 3.0.0 - 2018-05-02
-- Implementation of Hard fork on block 210000
-  - PIP - 0010: 50% inflation reduction
-  - PIP - 0011: 20% Development reward
-  - PIP - 0017: Anonymity via transaction mixing (multioperation)
-  - New target calc on protocol V3 in order to reduce the sinusoidal effect
-    - Harmonization of the sinusoidal effect modifying the rise / fall by 50% calculating over the last 10 blocks only when increase/decrease is high
-- New Safebox Snapshoting
-  - This allow quickly rollback/commit directly to Safebox instead of create a separate Safebox on memory (read from disk... use more ram...)
-  - Is usefull when detecting posible orphan blocks in order to check which chain is the highest chain without duplicating a safebox to compare
-- New Node network operations
-  - Get pending operations (code $0030)
-    - Implementation of the PIP-0013 (not exactly but with similar features)	
-  - Get account (code $0031)
-    - This call will allow a simple third party app communicate directly to a node to get account info (balance, n_operation, name, public key... )
-  - Reserverd codes from $1000 to $1FFF
-    - A node will not break connection if those codes are used, but will response with ERRORCODE_NOT_IMPLEMENTED ($00FF)
-- MultiOperation: PIP-0017
-  - Multioperation allows a transactional like operations, they can include transactions and change info operations in a signle multioperation
-    - Allow to send coins from N accounts to M receivers in a transaction mixing, without knowledge of how many coins where sent from "Alice" to "Bob" if properly mixed
-	- Ophash can be previously known by all signers before signing. They must sign only if multioperation includes it's transactions as expected 
-	- OpHash of a multioperation will allow to include n_operation and account of each signer account, but md160hash chunk will be the same for all
-- JSON-RPC changes:
-  - Added param "startblock" to "getaccountoperations" in order to start searching backwards on a specific block. Note: Balance will not be returned on each operation due cannot be calculated. Default value "0" means start searching on current block as usual
-  - Operation Object changes:
-    New fields:
-    - "senders" : ARRAY of objects - When is a transaction, this array contains each sender
-      - "account" : Sending Account 
-      - "n_operation"
-      - "amount" : PASCURRENCY - In negative value, due it's outgoing from "account"
-      - "payload" : HEXASTRING
-    - "receivers" : ARRAY of objects - When is a transaction, this array contains each receiver
-      - "account" : Receiving Account 
-      - "amount" : PASCURRENCY - In positive value, due it's incoming from a sender to "account"
-      - "payload" : HEXASTRING
-    - "changers" : ARRAY of objects - When accounts changed state
-      - "account" : changing Account 
-      - "n_operation"
-      - "new_enc_pubkey" : If public key is changed or when is listed for a private sale
-      - "new_name" : If name is changed
-      - "new_type" : If type is changed
-      - "seller_account" : If is listed for sale (public or private) will show seller account
-      - "account_price"	: PASCURRENCY - If is listed for sale (public or private) will show account price
-      - "locked_until_block" : If is listed for private sale will show block locked
-      - "fee" : PASCURRENCY - In negative value, due it's outgoing from "account"
-    Modified fields / DEPRECATED FIELDS
-    Caused by multioperation introduction, search in "senders"/"receivers"/"changers" instead
-    - "balance" will not be included when is not possible to calc previous balance of account searching at the past
-    - "signer_account" will not be included in Multioperations
-    - "account" : will not be included in Multioperations, use fields in "senders"/"receivers"/"changers" instead    
-    - "n_operation" will not be included in Multioperations, use fields in "senders"/"receivers"/"changers" instead
-    - "payload" will not be included in Multioperations, use fields in "senders"/"receivers"/"changers" instead
-    - "sender_account" is not correct to be used. Use "account" param on "senders" array instead
-    - "dest_account" is not correct to be used. Use "account" param on "receivers" array instead
-    - "amount" is not correct to be used. Use each "amount" param on "senders/receivers" instad. Note: sender "amount" is a negative number, positive for receiver
-  - New object "MultiOperation Object" : Will return info about a MultiOperation
-    - "rawoperations" : HEXASTRING with this single MultiOperation in RAW format
-    - "senders" : Will return an Array with Objects
-      - "account" : Sending Account 
-      - "n_operation"
-      - "amount" : In negative value, due it's outgoing from "account"
-      - "payload"
-    - "receivers"
-      - "account" : Receiving Account 
-      - "amount" : In positive value, due it's incoming from a sender to "account"
-      - "payload"
-    - "changers" : Will return an Array with Objects
-      - "account" : changing Account 
-      - "n_operation"
-      - "new_enc_pubkey" : If public key is changed
-      - "new_name" : If name is changed
-      - "new_type" : If type is changed
-    - "amount" : PASCURRENCY Amount received by receivers
-    - "fee" : PASCURRENCY Equal to "total send" - "total received"
-	- "signed_count" : Integer with info about how many accounts are signed. Does not check if signature is valid for a multioperation not included in blockchain 
-	- "not_signed_count" : Integer with info about how many accounts are pending to be signed
-    - "signed_can_execute"	: Boolean. True if everybody signed. Does not check if MultiOperation is well formed or can be added to Network because is an offline call
-  - New method "signmessage": Signs a digest message using a public key
-    - Params:
-      - "digest" : HEXASTRING with the message to sign
-	  - "b58_pubkey" or "enc_pubkey" : HEXASTRING with the public key that will use to sign "digest" data
-    - Result: False on error
-      - "digest" : HEXASTRING with the message to sign
-	  - "enc_pubkey" : HESATRING with the public key that used to sign "digest" data
-	  - "signature" : HEXASTRING with signature
-  - New method "verifysign": Verify if a digest message is signed by a public key
-    - Params:
-      - "digest" : HEXASTRING with the message to check
-	  - "b58_pubkey" or "enc_pubkey" : HEXASTRING with the public key that used to sign "digest" data
-	  - "signature" : HEXASTRING returned by "signmessage" call
-    - Result: False on error
-      - "digest" : HEXASTRING with the message to check
-	  - "enc_pubkey" : HESATRING with the public key that used to sign "digest" data
-	  - "signature" : HEXASTRING with signature
-  - New method "multioperationaddoperation": Adds operations to a multioperation (or creates a new multioperation and adds new operations)
-    This method does not need current Safebox state, so can be used offline or on COLD wallets when all info is provided
-    - Params:
-      - "rawoperations" : HEXASTRING (optional) with previous multioperation. If is valid and contains a single  multiopertion will add operations to this one, otherwise will generate a NEW MULTIOPERATION
-	  - "auto_n_operation" : Boolean - Will fill n_operation (if not provided). Only valid if wallet is ONLINE (no cold wallets)
-      - "senders" : ARRAY of objects that will be Senders of the multioperation
-        - "account" : Integer
-        - "n_operation" : Integer (optional) - if not provided, will use current safebox n_operation+1 value (on online wallets)
-        - "amount" : PASCURRENCY in positive format
-        - "payload" : HEXASTRING
-      - "receivers" : ARRAY of objects that will be Receivers of the multioperation
-        - "account" : Integer
-        - "amount" : PASCURRENCY in positive format
-        - "payload" : HEXASTRING
-      - "changesinfo" : ARRAY of objects that will be accounts executing a changing info
-        - "account" : Integer
-        - "n_operation" : Integer (optional) - if not provided, will use current safebox n_operation+1 value (on online wallets)
-        - "new_b58_pubkey"/"new_enc_pubkey": (optional) If provided will update Public key of "account"
-        - "new_name" : STRING (optional) If provided will change account name
-        - "new_type" : Integer (optional) If provided will change account type
-    - Result:
-      If success will return a "MultiOperation Object"
-  - New method "multioperationsignoffline"
-    This method will sign a Multioperation found in a "rawoperations"
-	Must provide info about accounts and keys (current Safebox state, provided by an ONLINE wallet)
-    - Params:
-      -	"rawoperations" : HEXASTRING with 1 multioperation in Raw format
-      - "accounts_and_keys"	: ARRAY of objects with info about accounts and public keys to sign
-        - "account" : Integer 
-        - "b58_pubkey" or "enc_pubkey" : HEXASTRING with the public key of the account
-    - Result:
-      If success will return a "MultiOperation Object"
-  - New method "multioperationsignonline"
-    This method will sign a Multioperation found in a "rawoperations" based on current safebox state public keys
-	Must provide info about accounts and keys (current Safebox state, provided by an ONLINE wallet)
-    - Params:
-      -	"rawoperations" : HEXASTRING with 1 multioperation in Raw format
-    - Result:
-      If success will return a "MultiOperation Object"
-  - New method "operationsdelete"
-    This method will delete an operation included in a Raw operations object
-    - Params:
-      -	"rawoperations" : HEXASTRING with Raw Operations Object
-    - Result:
-      If success will return a "Raw Operations Object"
-      - "rawoperations" : HEXASTRING with operations in Raw format
-      - "operations" : Integer
-      - "amount" : PASCURRENCY
-      - "fee" : PASCURRENCY  
-  - Updated method "getpendings" : Added params "start" (0..N) default=0 and "max" default=100 (0 = ALL)
-    - Also fixed bug #86 : https://github.com/PascalCoin/PascalCoin/issues/86
-  - New method "getpendingscount" : Returns pending operations count
-- Daemon:
-  - Allow to force max block read from Blockchain when started using "-b MAX_BLOCK_NUMBER" param. Example "nohup ./pascalcoin_daemon -r -b 12345 &"
-- Protections against invalid nodes (scammers):
-  - Protection on GetBlocks and GetBlockOperations
-- Merged new GUI with current stable core
-- New folders organization
-- Bugs solved
-
-### Build 2.1.9 - 2018-04-16
-- Searchs last valid block found on corrupted BlockChainStream.blocks file and allows to continue from last valid one. On prior versions, app halted and needed manually file deletion
-
-### Build 2.1.8 - 2018-04-16
-- Solved bug that can cause to corrupt BlockChainStream.blocks file when detecting an orphan block and creating new BlockHeaders row (every 1000 blocks). Very rare bug, but fatal error
-
-### Build 2.1.7 - 2018-04-10
-- Remove use of TPCOperation.FSignatureChecked introduced on 2.1.6 because is not 100% secure
-- Minor bugs
-
-### Build 2.1.6 - 2018-02-14
-- Important improvements
-  - Improved speed when processing operations on start
-  - Improved speed when processing pending operations after a new block found
-  - Deleted duplicate "SanitizeOperations" call
-  - Verify signed operations only once (TPCOperation.FSignatureChecked Boolean)
-  - Improvements in search methods of TOperationsHashTree
-    - Increase speed in search methods thanks to internal ordered lists
-    - Increase speed copying thanks to using FHashTree sender buffer instad of generating new one
-  - Internal bugs
-- Those improvements solved BUG that caused operations not included to blockchain due slow processing with MemPool 
-- NOTE: It's HIGHLY RECOMMENDED to upgrade to this version
-
-### Build 2.1.5 - 2018-02-09
-- GUI changes:
-  - Allow massive accounts "change info" operation
-  - Added "account type" and "sale price" on accounts grid
-  - Show "account type" stats on search account form  
-  - Changed Icon to current PascalCoin icon
-- Pending operations buffer cached to file to allow daemon/app restart without losing pending operations
-- Less memory usage thanks to a Public keys centralised buffer
-- JSON-RPC changes
-  - Added param "n_operation" to "Operation Object" JSON-RPC call
-  - New method "findnoperation": Search an operation made to an account based on n_operation field
-    - Params:
-	  - "account" : Account
-	  - "n_operation" : n_operation field (n_operation is an incremental value to protect double spend)
-	- Result:
-	  - If success, returns an Operation Object	  
-  - New method "findnoperations": Search an operation made to an account based on n_operation 
-    - Params:
-	  - "account" : Account
-	  - "n_operation_min" : Min n_operation to search
-	  - "n_operation_max" : Max n_operation to search
-	  - "start_block" : (optional) Block number to start search. 0=Search all, including pending operations
-	- Result:
-	  - If success, returns an array of Operation Object
-  - New method "decodeophash": Decodes block/account/n_operation info of a 32 bytes ophash
-    - Params:
-      - "ophash" : HEXASTRING with an ophash (ophash is 32 bytes, so must be 64 hexa valid chars)
-    - Result:
-      - "block" : Integer. Block number. 0=unknown or pending
-      - "account" : Integer. Account number
-      - "n_operation" : Integer. n_operation used by the account. n_operation is an incremental value, cannot be used twice on same account.
-      - "md160hash" : HEXASTRING with MD160 hash
-- Solved bug that caused to delete blockchain when checking memory 
-- Solved bug in Network adjusted time on receiving connections caused by full entry buffer
-- Minor optimizations
-
-### Build 2.1.3.0 - 2017-11-15
-- Fixed BUG when buying account assigning an invalid public key
-- Added maxim value to node servers buffer, deleting old node servers not used, this improves speed
-- Re-add orphaned operations back into the pending pool
-- RPC locking to prevent N_Operation race-condition on concurrent invocations
-- Minor bugs
-
-### Build 2.1.2.0 - 2017-07-27
-- No more blockchain in installer = TRUE DELETABLE BLOCKCHAIN (Safebox will be automatically downloaded by client from network)
-- Fixed storage bug when downloading a new safebox
-- Safebox will be downloaded in small chunks (aprox 2mb per chunk)
-- Read safebox file improvements (quick start)
-
-### Build 2.1.1.0 - 2017-07-16
-- Fixed installer bug: In last Windows installer a malformed safebox file was included. This build is only to provide a good safebox file with the installer
-- No important changes in exe/binary file 
-
-### Build 2.1.0.0 - 2017-07-14
-- Fixed bug of slow mass transactions from a single account due to incorrect sending order
-- Fixed memory leak on GetSafeBox request call
-- Added new GUI improvements on Operations form
-
-### Build 2.0.0.0 - 2017-06-23
-- MANDATORY UPGRADE - HARD FORK ACTIVATION WILL OCCUR ON BLOCK 115000
-- Introducing Protocol v2.
-  - https://github.com/PascalCoin/PascalCoin/blob/master/PascalCoinWhitePaperV2.pdf
-  - Core Changes:
-    - New safebox hash calculation algorithm to allow safebox checkpointing
-    - Improved difficulty target calculation to obtain a more stable average blocktime of 5 minutes, given abrupt hashpower fluctuations
-    - Bug-fix for China region users
-    - Anti-spam measures
-      - New Consensus Rule: A block can only contain 1 zero fee operation per sender account. If a sender account issues 2 or more zero-fee operations, that block is invalid.
-    - SafeBox now stored in chunks to facilitate checkpoint distribution
-	- Reintroduce orphan blocks operations on main blockchain
-  - Added Checkpointing:
-    - Checkpoint created on every 100'th block
-    - Added network operations to transfer Checkpoint chunks (compressed)
-  - Addded In-Protocol PASA Exchanging:
-    - New Operation: List Account, used to list an account for public or private sale 
-    - New Operation: Delist Account, used to delist an account from sale 
-    - New Operation: Buy Account, used to purchase an account lised for sale
-    - Updated Operation: Transaction, can be used in place of Buy Account operation in private account sales
-  - RPC API Changes:
-    - All changes are backwards-compatible for current 3rd-party infrastructure providers (exchanges, wallets).
-    - However, use of param "ophash" has been changed in V2, see "Operation Object changes" section to know how to use "old_ophash" param value    
-    - JSON changes:
-      - Account Object changes:
-        - Added param "state"  (values can be "normal" or "listed". When listed then account is for sale)
-        - If "state" is "listed" then will fill next values:
-          - "locked_until_block", "price", "seller_account" 
-          - "private_sale" : Boolean value 
-          - "new_enc_pubkey" : (Only on "private_sale" = true) - HEXASTRING with private sale encoded public key
-        - Added param "name": String
-          - Name available chars: abcdefghijklmnopqrstuvwxyz0123456789!@#$%^&*()-+{}[]\_:"|<>,.?/~
-          - Name first char: (cannot start with number): abcdefghijklmnopqrstuvwxyz!@#$%^&*()-+{}[]\_:"|<>,.?/~
-          - Name lenght: Empty or 3..64 chars length
-        - Added param "type": Integer (Valid values from 0..65535)
-      - Operation Object changes:
-        - Changed param "ophash": Current returned value of "ophash" is not the same than previous builds (changed calculation method)
-        - New param "old_ophash": Will return previous "ophash" value only for old blocks (prior to v2 protocol activation)
-        - New param "subtype" : Based on "optype" param, this param allows to discrimine point of view of operation (sender/receiver/buyer/seller ...)
-        - New param "signer_account" : Will return the account that signed (and payed fee) for this operation
-        - Param "enc_pubkey": Will return both change key and the private sale public key value
-        - About method "findoperation" and "ophash"
-          - Due to changed "ophash" param value calculation, method "findoperation" will find old "ophash" values too
-          - This is to avoid 100% compatibility, but remember that returned "Operation object" will contain "ophash" value calculated in new format only (you can read "old_ophash" value in older blocks)
-      - New methods:
-        - "listaccountforsale" : Lists an account for sale (public or private)
-          - Params:
-            - "account_target" : Account to be listed
-            - "account_signer" : Account that signs and pays the fee (must have same public key that listed account, or be the same)
-            - "price": price account can be purchased for
-            - "seller_account" : Account that will receive "price" amount on sell
-            - "new_b58_pubkey"/"new_enc_pubkey": If used, then will be a private sale
-            - "locked_until_block" : Block number until this account will be locked (a locked account cannot execute operations while locked)
-            - "fee","payload","payload_method","pwd"
-        - "signlistaccountforsale" : Signs a List an account for sale (public or private) for cold wallets
-          - Params: Same "listaccountforsale" params, and also:
-            - "rawoperations" : HEXASTRING with previous signed operations (optional)
-            - "signer_b58_pubkey"/"signer_enc_pubkey" : The current public key of "account_signer"
-            - "last_n_operation" : The current n_operation of signer account        
-        - "delistaccountforsale" : Delist an account for sale
-          - Params:
-            - "account_target" : Account to be delisted
-            - "account_signer" : Account that signs and pays the fee (must have same public key that delisted account, or be the same)
-            - "fee","payload","payload_method","pwd"
-        - "signdelistaccountforsale" : Signs a List an account for sale (public or private) for cold wallets
-		  - Params: Same "delistaccountforsale" params, and also:
-            - "rawoperations" : HEXASTRING with previous signed operations (optional)
-            - "signer_b58_pubkey"/"signer_enc_pubkey" : The current public key of "account_signer"
-            - "last_n_operation" : The current n_operation of signer account                      
-        - "buyaccount" : Buy an account previously listed for sale (public or private)
-          - Params: 
-            - "buyer_account","account_to_purchase",
-            - "price","seller_account",
-            - "new_b58_pubkey"/"new_enc_pubkey","amount",
-            - "fee","payload","payload_method","pwd"
-        - "signbuyaccount" : Signs a buy operation for cold wallets
-          - Params: Same "buyaccount" params, and also:
-            - "rawoperations" : HEXASTRING with previous signed operations (optional)
-            - "signer_b58_pubkey"/"signer_enc_pubkey" : The current public key of "buyer_account"
-            - "last_n_operation" : The current n_operation of buyer account	
-        - "changeaccountinfo" : Changes an account Public key, or name, or type value (at least 1 on 3)
-            - Params:
-            - "account_target" : Account to be delisted
-            - "account_signer" : Account that signs and pays the fee (must have same public key that target account, or be the same)
-            - "new_b58_pubkey"/"new_enc_pubkey": If used, then will change the target account public key
-            - "new_name": If used, then will change the target account name
-            - "new_type": If used, then will change the target account type
-            - "fee","payload","payload_method","pwd"
-        - "signchangeaccountinfo" : Signs a change account info for cold cold wallets
-          - Params: Same "changeaccountinfo" params, and also:
-            - "rawoperations" : HEXASTRING with previous signed operations (optional)
-            - "signer_b58_pubkey"/"signer_enc_pubkey" : The current public key of "account_signer"
-            - "last_n_operation" : The current n_operation of signer account
-        - "findaccounts" : Find accounts by name/type and returns them as an array of Account objects
-          - Returned array will be sorted by account number
-          - Params:
-            - "name" : (String) If has value, will return the account that match name
-            - "type" : (Integer) If has value, will return accounts with same type
-            - "start" : (Integer) Start account (by default, 0)
-            - "max" : (Integer) Max of accounts returned in array (by default, 100)
-      - Updated methods:
-        - "changekey" : Added param "account_signer" that allow to pay fee using another account with same public key than target "account" param. This allows to change keys on empty accounts (balance = 0) and pay fee
-        - "signchangekey" : Added param "account_signer", same use that in "changekey" method
-  - GUI changes:  (not available on daemon)
-    - New columns "name" and "type" on accounts
-    - Information about Accounts/Operation using F1
-    - Operations form now accepts:  (Will be active after V2 protocol activation)
-      - List account for sale (public or private)
-      - Delist account
-      - Buy account
-      - Change account name/type
-    - Operations form allows to search for accounts using F2 over an account edit box
-    - Changes in text showing operations information     
-- Other changes:
-  - Bug for china users fixed  
-  - Bugs fixed
-
-### Build 1.5.6.0 - 2017-05-03
-- Allow multiselect accounts (GUI wallet)
-- Priority for operations with fee:
-  - Allow miner server (pools) to select what to mine using pascalcoin_daemon.ini file (daemon only)
-    - RPC_SERVERMINER_MAX_OPERATIONS_PER_BLOCK: Max of operations that can be included in a block (Default 5000, min value 1000)
-    - RPC_SERVERMINER_MAX_ZERO_FEE_OPERATIONS: Max of operations with 0 fee that can be included in a block (Default 2000, min value 400)
-  - Operations with fee have always preference over 0 fee operations (will be mined first)
-  - If operations with fee fills all the buffer, then no zero fee operation will be included
-- Fixed bug on receiving big blocks and slow net connection to prevent never synchronize
-- Fixed bug on miner server that produces "invalid operations hash" error on valid solutions with 0 operations
-- Fixed bug on file storage
-- Fixed minor bugs
-
-### Build 1.5.5.0 - 2017-04-11
-- Corrected fee result on RPC calls as a negative number on "Change key" operations
-- Corrected PASCURRENCY value to be limited as a 4 decimal digits on RPC calls
-- JSON-RPC method "getaccountoperations" changed: if param "start" is -1, will include pending operations, otherwise not
-- Fixed bug: On "getaccountoperations" if an account had a lot of operations (receive tx included) then sometimes app crashed when executing depth search.
-  - Note: High depth search is slow because it search always starting from current state, going backwards, in order to return past balance. This can be a slow method on some account with high transactions volume.
-
-### Build 1.5.4.0 - 2017-03-14
-
-- Added Network Timestamp Adjustment (NAT) to calc valid timestamps
-  - Minimum 4 active connections to calc median used for NAT, otherwise use local timestamp
-  - Based on IP's (to prevent a malicious IP timejacking, each IP is only used once)
-  - Removed IP's and recalculated after disconnecting (to prevent malicious node connecting/disconnecting for timejacking)
-- New blocks will not be accepted if using future timestamp greater than NAT timestamp + 15 seconds (also, mantaining current protocol rule >= lastBlock.timestamp)
-- Network protocol fixed to 5-5 (Nodes with version prior to 1.5 will not be allowed)
-- Added protection for non included operations on a block, to prevent continuous sending. Only will resend operations once.
-- Bug #27 fixed: Invalid timestamp on FPC (https://github.com/PascalCoin/PascalCoin/issues/27)
-- JSON-RPC
-  - Method "getconnections" added "timediff" to know timestamp diff of node
-  - Method "payloaddecrypt" added "unenc_hexpayload" result value with HEXASTRING of unencrypted payload
-- Fixed some "Random Memory access violation errors" bugs found caused by multithreading and disconnected nodes
-
-### Build 1.5.3.0 - 2017-03-06
-
-- Fixed issue #23: RPC findoperation fails to find operation by opHash
-- Miners best practices: Sending new job with new timestamp every 30 seconds
-- Buffering last 10 sent jobs to miners
-- Small delay prior to destroy a connection to prevent exception handling
-- Minor logs changes
-
-
-### Build 1.5.2.0 - 2017-03-03
-
-- Added a jobs buffer for miners. This will allow to submit old job solutions (limited buffer). (Fix the "tx" issue)
-- Miner jobs will not be sent every time a transaction is received, thet will be buffered and sent every few seconds (Fix the "tx" issue)
-- Better network performance, allowing more operations and nodes thanks to buffering before relaying
-- Daemon: Allow select on ini file how many connections can handle
-- Fixed a locking when deleting connections
-
-### Build 1.5.1.0 - 2017-02-20
-
-- Memory leak fixed on RPC-JSON commands
-- Memory leak fixed on node connections
-- Improved network speed processing new blocks/operations
-- Some minor bugs
-
-### Build 1.5.0.0 - 2017-02-15
-
-- Net protocol upgrade to 4-5
-- Introducing "more work" with high priority than "more high". Work is calculated based on target. Higher target (more work) is more important than higher length
-- Solved locking/crash bug on high connections (caused by bad thread locking)
-- Improved network connection
-- Added JSON-RPC port 4003 protection Whitelist (only allowed IP's can use JSON-RPC)
-
-
-### Build 1.4.3.0 - 2017-02-02
-
-- Adding "maturation" param to "JSON Operation object", return null when operation is not included on a blockchain yet, 0 means that is included in highest block and so on...
-- Fixing miner timestamp value to prevent invalid time
-
-### Build 1.4.2.0 - 2017-01-23
-
-- Max JSON-RPC miner connections is now 1000 (before, 10)
-- JSON-RPC miner enabled at pascalcoin_daemon (linux daemon)
-- Screen messages for daemon
-- pascalcoin_daemon.ini file for daemon
-
-### Build 1.4.1.0 - 2017-01-18
-
-- Improved JSON communications with Miner client (Port 4009 by default)
-- Deleted adding numeration to JSON miner clients (only sends miner name)
-- Minor changes
-
-### Build 1.4.0.0 - 2016-12-30
-
-- JSON-RPC changes:
-  - Added method "signsendto" to allow a off-line wallet sign transaction operations without being syncrhonized
-  - Added method "signchangekey" to allow a off-line wallet sign change key operations without being syncrhonized
-  - Added method "executeoperations" to allow a on-line wallet execute operations signed off-line
-  - Added method "operationsinfo" that will decode operations signed off-line
-  - Added param "max" at JSON-RPC method "getblocks"
-  - Changed param name "deep" for "depht" in "getaccountoperations". Deep will be available for compatibility.
-  - Changed result for "changekeys". Now returns a "JSON operation object" array with each change key operation result
-  - Changes on "JSON Operation object": May return a "valid" param and "errors" param
-- Corrected a memory leak when processing JSON-RPC calls
-- Better performance in connection protocol
-- Updated protocol available to 1
-- Updated net protocol to 3-4
-- Important bug corrected
-
-### Build 1.3.0.0 - 2016-11-24
-
-- JSON-RPC modifications:
-  - New param "b58_pubkey", can be used instead of "enc_pubkey": b58_pubkey is a Base58 encoded public key with checksum, is the value that Wallet exports/imports public key
-  - New JSON object type Public Key: "name","can_use","enc_pubkey","b58_pubkey","ec_nid","x" and "y" for each public key
-  - Added params "start" and "max" to "getaccountoperations". By default deep=100, max=100 and start=0, so will return last 100 operations made to an account
-  - Added params "start" and "max" to "getblockoperations". By default max=100 and start=0, so will return last 100 operations made to a block
-  - Added params "start" and "max" to "getwalletaccounts". By default max=100 and start=0, so will return first 100 accounts of the wallet
-  - Added params "start" and "max" to "getwalletpubkeys". By default max=100 and start=0, so will return first 100 public keys of the wallet
-    - Will return a Public key JSON object
-  - Method "decodepubkey" allows params "enc_pubkey" or "b58_pubkey" (if used together, returns error if not match)
-    - Will return a Public key JSON object
-  - Method "changekey" allows params "new_enc_pubkey" or "new_b58_pubkey" (if used together, returns error if not match)
-  - Method "getwalletaccounts" allows params "enc_pubkey" or "b58_pubkey" (if used together, returns error if not match)
-  - Method "getwalletaccountscount" allows params "enc_pubkey" or "b58_pubkey" (if used together, returns error if not match)
-  - Method "getwalletcoins" allows params "enc_pubkey" or "b58_pubkey" (if used together, returns error if not match)  
-  - Method "payloadencrypt"  allows params "enc_pubkey" or "b58_pubkey" when payload_method="pubkey" (if used together, returns error if not match)  
-  - Method "addnewkey" changed. Does not return an HEXASTRING with enc_pubkey, now returns a public key JSON object
-  - New methods:
-    - Method "changekeys". Similar to "changekey" but for multiple accounts at param "accounts" as a coma separated string (ex: "accounts"="1248,1753,85056"). Returns a JSON object with result information
-    - Method "lock" to lock wallet. Returns true if locked, returns false if wallet has no password (an empty string, must put a new password prior to lock)
-    - New method "getwalletpubkey". Search for "enc_pubkey" or "b58_pubkey" and returns a Public key JSON object
-- Corrected a issue saving last 5 .bank files
-- Improved protections for .bank corruption files
-- Added "open data folder" button on options form
-- Other minor changes
-
-### Build 1.2.0.0 - 2016-11-16
-
-- Account checksum values modified to be more easy and more distributed: Checksum = ((N * 101) MOD 89)+10
-- Allow find operations by "ophash"
-- Show Operation "ophash" in operation payload decoder
-- Added param "enc_pubkey" to "getwalletaccounts" JSON-RPC method to return only accounts from this public key
-- Added params "pow" and "sbh" to "nodestatus" JSON-RPC method
-- Added method "getwalletaccountscount" returning accounts count of the entire wallet or for a single "enc_pubkey"
-- Added method "getwalletcoins" returning coins of the entire wallet or for a signle "enc_pubkey"
-- Modified seed nodes distribution to send only checked IP nodes
-- Corrected invalid operation block index when showing account operations
-
-
-### Build 1.1.0.0 - 2016-11-03
-
-- JSON-RPC Server included
-- Minor changes
-
-
-### Build 1.0.9.0 - 2016-10-21
-
-- Corrected a BUG (BUG-101) that causes blocking connections when received more than 100 connections, causing "alone in the world" after a cert period time.
-- It's necessary to update because new version will refuse old versions to make network stable.
-
-
-### Build 1.0.8.0 - 2016-10-20
-
-- Cross compatible
-- Can compile with Delphi or Lazarus (Free Pascal)
-- New storage system. No more access database
-- Network hashrate calculation
-
-
-### Build 1.0.7.0 - 2016-10-10
-
-- Introducing basic JSON-RPC to allow GPU miners development (Third party).
-- See file "HOWTO_DEVELOP_GPU_MINER_FOR_PASCALCOIN.txt"
-- No more CPU mining due exists GPU mining
-
-
-### Build 1.0.6.0 - 2016-10-04
-
-- Memory leaks corrections
-- Introducing net protocol 2-3
-- Source code modified, next build will be compiled with Lazarus and FPC
-
-
-### Build 1.0.5.0 - 2016-09-21
-
-- Massive operations, selecting multiple accounts
-- Filter accounts by balance
-- Correct operations explorer order of operations for each block (descending order)
-- Minor changes
-
-
-### Build 1.0.4.0 - 2016-09-16
-
-- IMPORTANT: Introducing net protocol changes: Must update!
-- More and more and more stable
-- Prevents "Alone in the world" if everybody is updated ;-)
-- Invalid local time detector with corrections
-- IP nodes configurator
-
-
-### Build 1.0.3.0 - 2016-09-08
-
-- Important changes to database 
-- Peer cache
-- Issues with Connections
-- More stable
-- Miner key selector
-- Invalid local time detector
-
-
-### Build 1.0.2.0 - 2016-08-31
-
-- Improved hashing speed
-- Allow mining without opening external ports
-- Choose how many CPU's want to mine
-- Show real-time pending operations waiting to be included in the block
-- More stable
-- Some miner modifications
-
-### Build 1.0.1.0 - 2016-08-12
-
-- Included an option to Import/Export Wallet keys file
-- Some miner modifications
-
-
-### Build 1.0.0.0 - 2016-08-11
-
-- First stable version.
-- Created with Genesis block hardcoded
-- Published at same time than Genesis block. NO PREMINE