fix inv meta
Limit damage of EntityPlayer memory leaks

If a plugin leaks EntityPlayer references by storing Player objects and never cleaning them up,
then the server will leak a ton of memory by buffering up packets into the outgoing queue that will
never be processed. These packets themselves then hold on to lots of other references, causing massive leaks.

This change does not prevent plugins from leaking EntityPlayer references, but will drastically reduce the impact
of the bug to the level one would expect of a Minecraft Server of memory leaks anyways.