Updating gitignore file.
Removing UIColor-Expanded dependency.

UIColor-Expanded by Erica Sadun is outdated and wasn't updated since March
2010 anymore. Some methods this category introduced exist since iOS 5 in UIColor
natively. So I figured out it isn't required for MAConfirmButton anymore at all.
However, I've implemented a fallback when MAConfirmButton is used on iOS
versions < iOS 5.