Using ARC

This pull request makes the code base compatible with ARC. This makes it much easier to integrate the source code directly into modern projects without having to mess with static libraries or frameworks.

The changes were mostly mechanical. The one major change was to get rid of the mallocs and use regular NSArrays, since I could not find a way to make ARC happy about a malloc'ed array that contained objects. If the performance in the shift reduce or goto tables suffers as a result, we could find a way to optimize this again.

The other minor change was to use NSString's rangeOfCharacterFromSet instead of CFStringFindCharacterFromSet, as the bridge was causing issues.

All unit tests pass.