Add RESTclient layer

It has a nice interface for doing work with APIs and whatnot

> This is a tool to manually explore and test HTTP REST webservices. Runs queries from a plain-text query sheet, > displays results as a pretty-printed XML, JSON and even images.
 
Checkoutt [Emacs Rocks!](http://emacsrocks.com/e15.html)
[Package Link](https://github.com/pashky/restclient.el)