x230: upgrade: detect development version if version higher than release

x230/upgrade.sh

@@ -64,7 +64,7 @@ fi
 if [[ "$CURRENT_VERSION" = "$UPSTREAM_VERSION" ]] ; then
 	echo -e "${GREEN}You are using the latest version of Skulls for the X230${NC}"
 	exit 0
-else
+elif [[ "$CURRENT_VERSION" < "$UPSTREAM_VERSION" ]] ; then
 	echo -e "${RED}You have ${CURRENT_VERSION} but there is version ${UPSTREAM_VERSION} available for the X230. Please update.${NC}"
 	read -r -p "Download it to the parent directory now? [y/N] " response
 	case "$response" in
@@ -83,4 +83,6 @@ else
 			exit 0
 		;;
 	esac
+else
+	echo "You seem to use a development version. Please use release package skulls-x230 ${UPSTREAM_VERSION} for flashing."
 fi