Build runtime Docker images.

Also added release process to push these images to GCS.

build/build-image/run-tests.sh

@@ -33,6 +33,8 @@ find_test_dirs() {
 
 cd "${KUBE_TARGET}"
 
+echo "+++ Running unit tests"
+
 if [[ -n "$1" ]]; then
   go test -cover -coverprofile="tmp.out" "$KUBE_GO_PACKAGE/$1"
   exit 0