Add Famo.us Implementation

Finally it has arrived, a PropertyCross implementation using the [Famo.us](http://famo.us) framework.

I have included screenshots of this for iOS 7, Windows Phone 8 and Android: https://github.com/matthewdunsdon/PropertyCross-Site/commit/b3e36174

Closes #274
Is this the 'standard' famous approach, or something you have assembled yourself?