CCFileUtils changes

NOTE: CCFileUtils not implemented on iOS, and will probably break the iOS build.

I am swamped with trying to get CocosPlayer for Android working before the release, so would really appreciate any help I could get with:

1. Porting CCFileUtils changes to iOS. They are almost exactly the same as CCFileUtils in cocos2d-iphone.
2. Testing all the projects with it. 

NOTE: resource directories have been modified to "resources-xsmall", "resources-small", "resources-medium", "resources-large", "resources-xlarge". These changes are being implemented in CocosBuilder right now. Should be done by tomorrow. Till then for testing, you can replace -large, with -ipad.

Thanks,

Rohan