Lemmo's Sell Greys

- Added option to remove the 12 items limitation (please use carefully)

    This option allows all selected items to sell at once.
    !!! Caution !!!
    Blizzard only allows a maximum of 12 items to be bought back.
    All items sold beyond this cannot be bought back. 
    Furthermore, it can sometimes cause problems to sell a large number of objects at once.

- the selling process is now slowed down a little to prevent errors by selling big amount of items