Adding a link to the NSScreencast episode about AFNetworking

Author: mattt

README.md

@@ -20,6 +20,7 @@ Choose AFNetworking for your next project, or migrate over your existing project
 - [Download AFNetworking](https://github.com/AFNetworking/AFNetworking/zipball/master) and try out the included Mac and iPhone example apps
 - Read the ["Getting Started" guide](https://github.com/AFNetworking/AFNetworking/wiki/Getting-Started-with-AFNetworking), [FAQ](https://github.com/AFNetworking/AFNetworking/wiki/AFNetworking-FAQ), or [other articles in the wiki](https://github.com/AFNetworking/AFNetworking/wiki)
 - Check out the [complete documentation](http://afnetworking.org/Documentation/) for a comprehensive look at the APIs available in AFNetworking
+- Watch the [NSScreencast episode about AFNetworking](http://nsscreencast.com/episodes/6-afnetworking) for a quick introduction to how to use it in your application.
 
 ## Overview