Bugfix: Corpse stays locked when looting fails

If looting fails either because of cooldown or there are items on your
cursor, the client is sent an end loot packet- the client releases the
corpse but no one else can loot. This simply resets BeingLootedBy in
this instance.
Merge remote-tracking branch 'origin/master' into Development
Added 'Not' bitmasks to simplify MapPossessions slot exclusion
Merge pull request #274 from RicardoCampos/Development

Bugfix: Corpse stays locked when looting fails
Take into account endurance bonuses from AAs
Fixed stacking issue in world tradeskill containers. (Added #peekinv world)
Merge branch 'master' of https://github.com/EQEmu/Server into InvV2Phase1