title: UIScrollView with touchesMoved not called
body: <p>I've a UIScrollView that contains an UIImageView. 
  The UIScrollView lets zooming and panning through the UIImageView.</p>
  
  <p>The problem is that I would like know the finger movement every time, and I'm trying to catch the event with touchesMoved method.
  But it's not working, despite touchesBegan and touchesEnded that are called correctly.</p>
  
  <p>In fact, touchesMoved is called if the finger movement is really small, and the UIScrollView doesn't started panning. At the moment that UIScrollView starts getting moved, the event stops being called.</p>
  
  <p>Somebody know what's the problem and how to fix it?
  I've thought that maybe the UIImageView inside is catching the event or something like that.</p>