Bug: Incorrect event-signature for 'nodedrop' in Ext.tree.TreePanel
(it looks like a guy can use 'beforenodedrop' instead)

****************************************************************
* EDIT: my bad. all the event params are packed up into a single object.
* eg:
* onNodeDrop :function(dropEvent) {
* alert('source: ' + dropEvent.source);
* alert('target: ' + dropEvent.target);
* }
****************************************************************
Ext.tree.TreePanel docs say:
Code:
nodedrop
public event nodedrop
Fires after a DD object is dropped on a node in this tree. The dropEvent passed to handlers has the following properties:

    * tree - The TreePanel
    * target - The node being targeted for the drop
    * data - The drag data from the drag source
    * point - The point of the drop - append, above or below
    * source - The drag source
    * rawEvent - Raw mouse event
    * dropNode - Dropped node(s).

Subscribers will be called with the following parameters:

    * dropEvent : Object

This event is defined by TreePanel.
Ext.tree.DropZone does this:
Code:
completeDrop : function(de){
        var ns = de.dropNode, p = de.point, t = de.target;
        if(!(ns instanceof Array)){
            ns = [ns];
        }
        var n;
        for(var i = 0, len = ns.length; i < len; i++){
            n = ns[i];
            if(p == "above"){
                t.parentNode.insertBefore(n, t);
            }else if(p == "below"){
                t.parentNode.insertBefore(n, t.nextSibling);
            }else{
                t.appendChild(n);
            }
        }
        n.select(); // select and highlight the last insert
        if(this.tree.hlDrop){
            n.ui.highlight();
        }
        t.ui.endDrop();
        this.tree.fireEvent("nodedrop", de);  // <------------ INCORRECT EVENT SIGNATURE
    },