title: MapsForge 0.4.0: is it possible to implelment a Marker 's onTap event?
body: <p>i'm using MapsForge latest branch (master) and i'd like to implement a Marker's onTap event.
  I think it was possible on 0.3.0, but i can't use 0.3.0 because i use a different Drawable for each Marker on the map.</p>
  
  <pre><code>ArrayList&lt;Monument&gt; monuments = getMonuments(); 
  
  mListOverlay = new ListOverlay();
  ArrayList&lt;OverlayItem&gt; markers = new ArrayList&lt;OverlayItem&gt;();          
  
  for(Monument m : monuments){
      GeoPoint gp = new GeoPoint(m.getLat(), m.getLon());
      Marker m = createCustomMarker(R.drawable.marker, gp, p.getNumber()));
      markers.add(m);     
  }
  
  mListOverlay.getOverlayItems().addAll(markers);
  
  mMapView.getOverlays().add(mListOverlay);
  </code></pre>
  
  <p>"createCustomMarker" returns a Marker that uses a Drawable with a number on top.</p>
  
  <p>Anyone knows how i can override the behaviour of "m" when it is tapped?</p>
  
  <p>Remember: branch master! not 0.3.0!!</p>
  
  <p>Thanks</p>