Provided option to manually specify revision hash for source packages…

… and tarballs

version.pri

@@ -1,12 +1,15 @@
 APP_VERSION = 0.1
+APP_REVISION = $(shell hg identify -i)
+#uncomment the below line in a source package and fill-in the correct revision
+#APP_REVISION = <rev-hash>
 APP_VERSION_FILE = version.cpp
 revtarget.target = $$APP_VERSION_FILE
 win32:revtarget.commands = echo "const char *version = \"$$APP_VERSION\";" \
-	"const char *revision = \"$(shell hg identify -i)\";" \
+	"const char *revision = \"$$APP_REVISION\";" \
         > $$APP_VERSION_FILE
 unix:revtarget.commands = echo \
         "\"const char *version = \\\"$$APP_VERSION\\\";" \
-	"const char *revision = \\\"$(shell hg identify -i)\\\";\"" \
+	"const char *revision = \\\"$APP_REVISION\\\";\"" \
         > $$APP_VERSION_FILE
 revtarget.depends = $$SOURCES $$HEADERS $$FORMS $$POST_TARGETDEPS