Print engine version to stdout when starting Godot

Also include website URL and make it configurable via version.py
together with the rest of the engine branding.

Add mention to MIT license in --help output.

main/main.cpp

@@ -204,7 +204,8 @@ void finalize_physics() {
 
 void Main::print_help(const char *p_binary) {
 
-	print_line(String(VERSION_NAME) + " v" + get_full_version_string() + " - https://godotengine.org");
+	print_line(String(VERSION_NAME) + " v" + get_full_version_string() + " - " + String(VERSION_WEBSITE));
+	OS::get_singleton()->print("Free and open source software under the terms of the MIT license.\n");
 	OS::get_singleton()->print("(c) 2007-2019 Juan Linietsky, Ariel Manzur.\n");
 	OS::get_singleton()->print("(c) 2014-2019 Godot Engine contributors.\n");
 	OS::get_singleton()->print("\n");
@@ -1091,6 +1092,9 @@ error:
 
 Error Main::setup2(Thread::ID p_main_tid_override) {
 
+	// Print engine name and version
+	print_line(String(VERSION_NAME) + " v" + get_full_version_string() + " - " + String(VERSION_WEBSITE));
+
 	if (p_main_tid_override) {
 		Thread::_main_thread_id = p_main_tid_override;
 	}

methods.py

@@ -61,6 +61,7 @@ def update_version(module_version_string=""):
     f.write("#define VERSION_BUILD \"" + str(build_name) + "\"\n")
     f.write("#define VERSION_MODULE_CONFIG \"" + str(version.module_config) + module_version_string + "\"\n")
     f.write("#define VERSION_YEAR " + str(version.year) + "\n")
+    f.write("#define VERSION_WEBSITE \"" + str(version.website) + "\"\n")
     f.close()
 
     # NOTE: It is safe to generate this file here, since this is still executed serially

version.py

@@ -5,3 +5,4 @@ minor = 2
 status = "dev"
 module_config = ""
 year = 2019
+website = "https://godotengine.org"