* URLDownloadList - set an update on both items when the priority is
increased or decreased
   - added a function for visibleSize: which counts the number of items
not deleted
   - moved item to the end of the array when it is deleted, as it's not
fully deleted, till a system save
* DataStorage - removed destination from delete statement for download,
as it was not deleting it
* CLDownloadMenu - fixed menu traversal