optimized menu function to do the DOM manipulation in the document fragment

* Removed need for event ```loaded.wb``` since the preprocessing task was rewritten to happen after the ajaxed in event
* Optimized the ```.clone()``` to a string variable since ```.clone``` copies events and data which is not required an introduces a bit of overhead that is not required since this function is simply copying the html
* Corrected the placement of the copied element to be above the ```.wb-nav``` instance instead of below the close indicator to allow for other elements to be placed before the copied element.