iPhone Sample Project

This pull request adds support for the 4" and 3.5" screen sizes to the sample project.

![keynote 001](https://cloud.githubusercontent.com/assets/522951/3295869/1796e3bc-f5cc-11e3-8c74-c1766d057321.jpg)

It also makes some minor changes to the iPad layout. These changes are present to keep the layout code between iPhone and iPad similar.

![keynote 002](https://cloud.githubusercontent.com/assets/522951/3295872/2643319a-f5cc-11e3-8a55-53d3d5563d73.jpg)