title: update markercluster after removing markers from array
body: <p>I am currently using markercluster plugin with jquery ui maps.</p>
  
  <p>I have two arrays one of all markers (called markers) and one of markers that match search criteria (called current_markers). These are fitered from the first array.</p>
  
  <p>I then draw the current_markers on screen.</p>
  
  <p>I am finding however that the markerclusterer library is not updating based on this change.</p>
  
  <p>So how can I update the markerclusterer?</p>
  
  <p>Is it possible to assign the markerclusterer to a variable and call an update function?</p>