endpoints: add comment to openapi.yaml about deploying on App Engine (#252)
endpoints: add comment to openapi.yaml about deploying on App Engine (#252)


adamyanliev/golang-samples,GoogleCloudPlatform/golang-samples,danicat/golang-samples,GoogleCloudPlatform/golang-samples,danicat/golang-samples,adamyanliev/golang-samples,adamyanliev/golang-samples,GoogleCloudPlatform/golang-samples,adamyanliev/golang-samples,danicat/golang-samples