Possible 1.0.0 release

Hi,

I needed to work with some zip files so I looked over your library. It was easy to understand it but it wasn't using the latest technologies so I did the following:
- use Xcode 5 with module, image assets etc
- use ARC only and drop manual reference counting support
- class prefix
- drop exception support and implement NSError handling

I plan to:
- add more error codes
- write functions without the NSError param
- write unit tests

Since I think this code would help other developers I recommend merging this changes into your repo.
Any feedback is welcome!