Started the Restkit integration

**Useful info**: https://gist.github.com/chourobin/4727113
## What? Why?
New stack that supports the integration with RestKit

## What should be tested?
- [x] New stack has tests and they pass
- [x] New stack works integrated with RestKit

![gif](http://media.giphy.com/media/7sC5l8ZZKMzXG/giphy.gif)