dojo.dnd.Container: callback functions onItemInsert, onItemDelete

[chucky]

Currently it is not straightforward to trigger some user action when an item is inserted into or deleted from the container. To this end I propose that Container constructor recognizes additional parameters: onItemInsert and onItemDelete of type function(container, data [,thisObj]). These callback functions would be called on insertion and deletion of an item, respectively.

See also http://dojotoolkit.org/forum/dojo-core-dojo-0-9/dojo-core-development-discussion/suggestion-dojo-dnd-container-callback-fun

[elazutkin]

Moving all open ticketd to the future.