Using GLKit in RubyMotion

Experiments using GLKit

This is basically a port of Ray Wenderlich's code in his nice GLKit tutorial.

One of the more interesting parts are the use of Pointer objects to pass vertex buffers. It's not beautiful (a bit ugly, actually), but at least RubyMotion does provide a mechanism to interface with pointer based C apis like this. It'd be interesting to see what kinds of nice ruby abstractions we could build on this.

-Pete