added Makefile

Makefile

@@ -0,0 +1,18 @@
+#!make
+include Makefile.env
+
+# Put it first so that "make" without argument is like "make help".
+build: docker-build
+release: docker-build docker-release
+
+.PHONY: docker-build docker-release
+
+docker-build:
+	docker build --build-arg VERSION="${version}" \
+				 -t "${CONTAINER_REPOSITORY}:${version}" \
+				 -t "${CONTAINER_REGISTRY}/${CONTAINER_REPOSITORY}:${version}" \
+				 .
+	docker image prune -f
+
+docker-release:
+	docker push ${CONTAINER_REGISTRY}/${CONTAINER_REPOSITORY}:${version}

Makefile.env

@@ -0,0 +1,5 @@
+NAME                  = markdown-to-confluence
+IMAGE_SOURCE          = https://github.com/vmware-tanzu-labs/markdown-to-confluence
+CONTAINER_REGISTRY    = ghcr.io/vmware-tanzu-labs
+CONTAINER_REPOSITORY  = markdown-to-confluence
+version               = latest