title: UIButton responds to UIPanGestureRecognizer on top of it
body: <p>I just added a UIView with UIPanGestureRecognizer on top of my view.<br>
  The view has several UIButtons which respond to touchUpInside events.<br>
  What's weird is that ever since I brought the UIPanGestureRecognizer, when panning, if the UIButton is right underneath the "Panning view", the button would trigger which is not what I am after. 
  Of course I could make a BOOL flag for "panning", so that the button won't fire, but it seems to me like bad engineering and surely something I am missing. I guess after the first touch, both views intercept the event.<br>
  Is it possible to overcome this?</p>
  
  <p>Thanks</p>