Implement version information storage and retrieval for the bootrom and the osimage.

Use perl to create the version information (thereby re-creating the perl dependency and adding an svn dependency) but fall back in case of missing perl or svn

bootrom/Makefile

@@ -2,7 +2,7 @@
 
 # DO NOT use thumb mode in the phase 1 bootloader since that generates a section with glue code
 ARMSRC = fromflash.c 
-THUMBSRC = usb.c bootrom.c
+THUMBSRC = usb.c version.c bootrom.c
 ASMSRC = ram-reset.s flash-reset.s
 
 # Do not move this inclusion before the definition of {THUMB,ASM,ARM}SRC
@@ -19,8 +19,9 @@ clean:
 	$(DELETE) $(OBJDIR)$(PATHSEP)*.s19
 	$(DELETE) $(OBJDIR)$(PATHSEP)*.map
 	$(DELETE) $(OBJDIR)$(PATHSEP)*.d
+	$(DELETE) version.c
 
-.PHONY: all clean help
+.PHONY: all clean help 
 help:
 	@echo Multi-OS Makefile, you are running on $(DETECTED_OS)
 	@echo Possible targets: