cleaned up and fixed collisions with brush models (example: you can now ramp jump...

cleaned up and fixed collisions with brush models (example: you can now ramp jump and hit the light fixture in e4m1 in dp mod), now uses 3 different bounding boxes for the trace (hullmins/hullmaxs for collisions with brush models, mins/maxs for collisions with normal entities, mins2/maxs2 for collisions with monsters), and the movebounds use the largest of the bounding boxes to ensure proper collisions
items suspended in the air on a func_door (or similar) entity which is then killed by a trigger, should now continue floating in the air (this is a gross hack, to make suspended items in various maps stay in the air)

git-svn-id: svn://svn.icculus.org/twilight/trunk/darkplaces@1820 d7cf8633-e32d-0410-b094-e92efae38249