[9584] Continue fix loot roll packets and related code.
* Propertly send itemSlot field and use it with looted target for roll selection.
* Remove references to NumberOfPlayers useless data send in args
* Fixed long existed bug with roll show when single player from group can roll item.
* Fixed possible crash at player leave group while item roll
* Fixed wrong item amount in stack in rolls inreasult use non-initilized field as info source.
* Remove unused item guid field from Roll and not lost for nothing item guids for this.
Thanks for help in research to TOM_RUS and j4r0d.