title: How to fires event after Drag & Drop on TreePanel
body: <p>How can I use Ext.tree.ViewDDPlugin's events?</p>
  
  <p>I have a TreePanel that uses DDPplugin, but I'd like to know how to listen to the drop event.</p>
  
  <p>This is what my code looks like:</p>
  
  <pre><code>var monPretree = Ext.create('Ext.tree.Panel',{
              id : 'treepanel',
              title : 'TITRE',
              //width : 800,
              //height : 600,
              width : 500,
              enableDD: true,
              useArrows : true,
              viewConfig : {
                  plugins : {
                      ptype: 'treeviewdragdrop',     
                        appendOnly: true,     
                        listeners: {       
                          drop: function (node, data, overModel, dropPosition) {         
                                alert('CHANGE');       
                          },       
                          notifyDrop: function (dragSource, event, data) {         
                                var nodeId = data.node.id;         
                                alert(nodeId);       
                          },       
                          notifyOver: function (dragSource, event, data) {         
                              alert('over');
                          }     
                      }   
                  }
  
              },
              singleExpand : false,
              store : monPrestore,
              rootVisible : false,
  </code></pre>
  
  <p>I would like to fire drop events for example, but my code doesn't work</p>
  
  <p>Thanks :)</p>