Adds reference to slack channel in readme

README.md

@@ -38,6 +38,10 @@ Read the docs on our [Docs site](https://pusher.github.io/oauth2_proxy).
 
 ![OAuth2 Proxy Architecture](https://cloud.githubusercontent.com/assets/45028/8027702/bd040b7a-0d6a-11e5-85b9-f8d953d04f39.png)
 
+## Getting Involved
+
+If you would like to reach out to the maintainers, come talk to us in the `#oauth2_proxy` channel in the [Gophers slack](http://gophers.slack.com/).
+
 ## Contributing
 
 Please see our [Contributing](CONTRIBUTING.md) guidelines.