* Added Mobj::copyPosition and MobjCollection::moveToRandom
* itemrespawnat field for EDF thingtypes allows Raven-style respawning items to appear at any one of a thing in a collection on the map.
* Added itemrespawnat property to HWeaponFireMace.
* Ignore *.opensdf in vc2012 folder

git-svn-id: http://mancubus.net/svn/hosted/eternity/trunk@2653 86ba831e-150c-0410-ab35-e06eaae15ed9
HereticMaceSpots need to not be NOSECTOR too, or else they just stay up in the air when floors move, thanks to BOOM logic... 9_9

git-svn-id: http://mancubus.net/svn/hosted/eternity/trunk@2654 86ba831e-150c-0410-ab35-e06eaae15ed9
* Start work on Heretic cheats
* Added BEX mnemonics for Heretic cheat messages
* Some cleanup in d_dehtbl.cpp
* Change from SGI STL hash to sdbm, which profiled as the second fastest hash given input of the entire English dictionary, and had one of the fewest number of collisions.

git-svn-id: http://mancubus.net/svn/hosted/eternity/trunk@2655 86ba831e-150c-0410-ab35-e06eaae15ed9