Category Prefixes

The [Apple docs](https://developer.apple.com/library/ios/documentation/cocoa/conceptual/ProgrammingWithObjectiveC/CustomizingExistingClasses/CustomizingExistingClasses.html#//apple_ref/doc/uid/TP40011210-CH6-SW4) recommend prefixing methods in categories with your 3-letter namespace to avoid collisions with other libraries.

I have two commits here. The first just renames the methods, avoiding the potential namespace collision. The second further applies the 3-letter namespace to the category names and files themselves. That one is mainly just for naming conventions and consistency.