Complete revamp after iOS7 and SpriteKit announcement

No longer supporting Cocos2d.
Merge branch 'master' of https://github.com/jcrowson/adventurekit

Conflicts:
	Inventory.h
	Inventory.m
	cocos2d-2.x-ARC-iOS.xcodeproj/project.pbxproj
	cocos2d-2.x-ARC-iOS/AppDelegate.m
	cocos2d-2.x-ARC-iOS/Constants.h
	cocos2d-2.x-ARC-iOS/HelloWorldLayer.m