title: SKPhysicsBody containment test?
body: <p>Any simple method to test if an SKPhysicsBody <strong>entirely contains another</strong>?</p>
  
  <p>Something like <code>bodyA</code> contains every point of <code>bodyB</code>, or so.</p>
  
  <p>Just wanted to ask you before implement some 2D math helpers to do this with additional "meta"-CGPaths attached to a given node or something.</p>