title: ClusterManager repaint markers of Google maps v2 utils
body: <p>I'm making a server request and when I receive the response from server, I'm executing on UI Thread a <code>ClusterManager.addItem()</code> but this items are not painting in the map, only when I make a zoom update (+,-) newly added items starts appearing. I also tried to debug the renderer, but <code>onBeforeClusterRendered</code> / <code>onBeforeClusterItemRendered</code> are not getting called until I update the zoom in map.</p>
  <p>Any ideas how to refresh map/clusterManager/markers?</p>
  <pre class="lang-java prettyprint-override"><code>MarkerManager markerManager = new MarkerManager(map);
  clusterManager = new ClusterManager&lt;TweetClusterItem&gt;(getActivity(), map, markerManager);
  clusterManager.setRenderer(new TweetClusterRenderer(getActivity(), map, clusterManager, defaultMarker));
  clusterManager.setOnClusterClickListener(this);
  clusterManager.setOnClusterInfoWindowClickListener(this);
  clusterManager.setOnClusterItemClickListener(this);
  clusterManager.setOnClusterItemInfoWindowClickListener(this);
  
  UiSettings uiSettings = map.getUiSettings();
  uiSettings.setZoomControlsEnabled(true);
  uiSettings.setMyLocationButtonEnabled(false);
  
  map.setOnCameraChangeListener(clusterManager);
  map.setOnMarkerClickListener(clusterManager);
  map.setOnInfoWindowClickListener(clusterManager);
  map.setOnMapClickListener(this);
  </code></pre>