Document and implement HAL on iOS

[mattapperson]

HAL is great, but just building it is not enough. We must build it FOR something. Namely in this instance iOS.

This issue must supply:

• The code itself
• Documentation
• Tests

[mattapperson]

The goal -> https://gist.github.com/kwhinnery/9399280

[mattapperson]

So far we have HAL running on iOS and are working to get some of the tests ported over as well as a HAL POC of the Ti API for windows views and buttons running in a HAL based app