feat: release tool (#3)

* untested release tool

* update PHONY

* show diff and fix v

Makefile

@@ -21,4 +21,15 @@ time: build
 
 .PHONY: valgrind
 valgrind: build
-	valgrind --leak-check=full -s ./build/$(TARGET) $(TEST_ARGS)
+	valgrind --leak-check=full -s ./build/$(TARGET) $(TEST_ARGS)
+
+.PHONY: release
+release: clean build time
+	@echo -n "Version (x.y.z): "
+	@read VERSION; \
+		sed -i "s/#define VERSION.*/#define VERSION \"v$$VERSION\"/g" ./src/const.h; \
+		git add ./src/const.h; \
+		git diff origin/master; \
+		git commit -m "$(TARGET) v$$VERSION"; \
+		git tag v$$VERSION -m "$(TARGET) v$$VERSION"
+	@echo updated ./src/const.h and tagged version