title: markerClusterer on click zoom
body: <p>I just added a MarkerClusterer to my google map. It works perfectly fine.</p>
  
  <p>I am just wondering if there is any way of adjusting the zoom-in behaviour when the cluster is clicked. I would like to change the zoom level if possible.</p>
  
  <p>Is there any way of achieving this?</p>
  
  <p>Thanks</p>