title: MKAnnotation - Map Pin callout pops up behind other map pins
body: <p>My map pins can be quite densely populated so that when a pin is selected the callout pops up but is mostly obscured by all the other map pins - I can bring the Map Pin to the front it there were a delegate for selected map pin ( not tapped callout, selected pin ).</p>
  
  <p>Any suggestions for a work around ?</p>