title: Box2D implementation issue
body: <p>I am trying to put Box2D into my app. I have the Box2D folder from the latest Cocos2D release. I drag it into my project and I add it to the destination group folder and I get 4 errors, it is where the compiler can't find b2Collision.h, b2BroadPhase.h, and b2Collision.h, I know there are 2 errors for the collision. There is another error but it comes and goes based upon how to implement it.
  Anyway, with the way I am implementing it, how do I get rid of these errors? Does anyone have any ideas/tips?</p>
  
  <p>Thanks!!!</p>