Fixing Master Loot for already assigned item to players who had full bags.

A bug was still present, master looters assigning items to players with full inventory
were still able to change the target if they wanted to. Now, only the winner will be able
to pick up the loot once it's assigned.
Merge pull request #247 from Warkdev/Rel20

Fixing Master Loot for already assigned item to players who had full bags