Upgrade UI to Storyboard for Demo, Add Unit Tests to Demo, Add Color Mixer to Demo, Add colorWithRGBADict: Constructor

Replace .xib file with .storyboard file and update all UIViewController subclasses. Add Unit tests to Demo app as XCTest. Add new tab to Demo App called schemes which allows user to mix an RGB colour and see color schemes generated in realtime. Update ReadMe with new screenshots. Apply prominent coding standards to all source code. Add colorWithRGBADict constructor. Fix colorWithRGBAArray constructor.

![iphone-1](https://f.cloud.github.com/assets/1225755/1483935/87acf5f0-46ff-11e3-840d-1ec868e2015c.png)