Makefile.defs: version set to 5.0.0-dev0

- development for next major release 5.0.0 is open

Makefile.defs

@@ -94,10 +94,10 @@ SCTP ?= 1
 INSTALL_FLAVOUR=$(FLAVOUR)
 
 # version number
-VERSION = 4
-PATCHLEVEL = 4
+VERSION = 5
+PATCHLEVEL = 0
 SUBLEVEL =  0
-EXTRAVERSION = -pre3
+EXTRAVERSION = -dev0
 
 # memory manager switcher
 # 0 - f_malloc (fast malloc)