Starts refactoring for more complicated structure.

We'll need other singletons later (eg Twitter), so I'm grouping those.
The Sprite classes are also about to become more than plain sprites,
and to inherit from a common parent, thus the Objects group.
Add a constant for detecting whether we are in debug mode.
Common protocols file added.

This is used to keep loose coupling between classes.
Adds shared parent class for Hero and Projectile.
Removing a few imports that are no longer needed.
Refactor the GameState singleton to use iOS's dispatch_once.
Placeholder code for the Hero's state machine and interactions.
Adds GameManager class.

The GameManager is used to decouple scenes from eachother.
Moved scene shortcuts in with the other enums.
Moved the Hero's Box2D setup inside the hero.

The GameLayer (and wider world) shouldn't care about the Hero's physics
setup. Also reduces cruft in the GameLayer.
Moves projectile physics setup code into Projectile class.
Adds texture atlases for the gameplay sprites.

Closes #41 and closes #28.
Adds animations for the Hero.
Match filesystem to project.

Moved *.plist files into Plists directory.
Convert #Warrior to using ARC.

Disable ARC with the compiler flag -fno-objc-arc on cocos2d.
Add cocod2d as a cross project reference.

This makes it easier to upgrade cocos2d in the future as well as
seperates out the build configuration (e.g. build cocos2d without ARC
and #Warrior with ARC).

It does however increase the depot size significantly.
Merging restructure branch into twintegration branch
Convert #Warrior to using ARC.