feat(Makefile): add build-stable target

To upload/overwrite the `deis-stable-*` binaries on each release, in a similar manner as we do for `latest`/master commits.

(Not tied to the keyword `stable` and open to suggestions for better naming)

Author: Vaughn Dice

Makefile

@@ -46,6 +46,11 @@ build-revision:
 	$(eval GO_LDFLAGS = -ldflags '-X ${repo_path}/version.Version=${GIT_TAG}-${REVISION}')
 	gox -verbose ${GO_LDFLAGS} -os="${BUILD_OS}" -arch="${BUILD_ARCH}" -output="${DIST_DIR}/${REVISION}/deis-${REVISION}-{{.OS}}-{{.Arch}}" .
 
+# This is supposed to be run within a docker container
+build-stable:
+	$(eval GO_LDFLAGS = -ldflags '-X ${repo_path}/version.Version=${GIT_TAG}')
+	gox -verbose ${GO_LDFLAGS} -os="${BUILD_OS}" -arch="${BUILD_ARCH}" -output="${DIST_DIR}/deis-stable-{{.OS}}-{{.Arch}}" .
+
 # This is supposed to be run within a docker container
 build-tag:
 	$(eval GO_LDFLAGS = -ldflags '-X ${repo_path}/version.Version=${GIT_TAG}')