Cleanup instructions added (GoogleCloudPlatform#202)

* Cleanup instrucions added

Signed-off-by: Ihor Dvoretskyi <ihor@linux.com>

* Update README.md

README.md

@@ -254,6 +254,15 @@ by deploying the [release manifest](./release) directly to an existing cluster.
    curl -v "http://$INGRESS_HOST"
    ```
 
+### Cleanup
+
+If you've deployed the application with `skaffold run` command, you can run
+`skaffold delete` to clean up the deployed resources.
+
+If you've deployed the application with `kubectl apply -f [...]`, you can
+run `kubectl delete -f [...]` with the same argument to clean up the deployed
+resources.
+
 ## Conferences featuring Hipster Shop
 
 - [Google Cloud Next'18 London – Keynote](https://youtu.be/nIq2pkNcfEI?t=3071)