Add running-in-cluster=false option.

controllers/nginx/README.md

@@ -18,6 +18,16 @@ This is a nginx Ingress controller that uses [ConfigMap](https://github.com/kube
 - default backend [404-server](https://github.com/kubernetes/contrib/tree/master/404-server)
 
 
+## Dry running the Ingress controller
+
+Before deploying the controller to production you might want to run it outside the cluster and observe it.
+
+```console
+$ make controller
+$ mkdir /etc/nginx-ssl
+$ ./nginx-ingress-controller --running-in-cluster=false --default-backend-service=kube-system/default-http-backend
+```
+
 
 ## Deploy the Ingress controller