#25

1. height and parent added to Cluster Node
2. createCluster is called after load.
3. In the render the renderClusterMethod is called. 
4. In the render Cluster method the clusters are rendered recursively
5. The Timeline is drawn with some shifts of the height of the root cluster.  
6. Dataobject hovered is now on users ( Need fixing)
7. Mouse Drag events are disabled