* Refactoring of ZoneObject as earlier suggested by DavidPH to support an overloaded operator new for passing in full zone allocation data (tag, user).
* Thinker now overrides ZoneObject::operator new (size_t) to allocate itself at PU_LEVEL tag.
* Fixed memory leak in R_InitTranMap. Removed caching in tranmap.dat to simplify code, and also ensure that the map is only rebuilt when actually necessary.

git-svn-id: http://mancubus.net/svn/hosted/eternity/trunk@2466 86ba831e-150c-0410-ab35-e06eaae15ed9