* Only change texture when stationary or moving down, for additional fidelity to source material. This has zero overhead, and actually might REDUCE lag in some circumstances... my nitpickiness wins again.
* Apply ML_EFFECT1 to it to make it invisible and intangible (removing (FF_SOLID|FF_RENDERALL|FF_CUTLEVEL) from it) from every side except the bottom. Becomes visible and tangible when it's hit once. Might fuck over players in mp, but really our Mario blocks are so high in the air (and we'd need to update Pipe Towers to take advantage anyways) that they're super unlikely to get a kill this way
* Checks for the Brick Block have been switched over to the presence of FF_SHATTERBOTTOM instead of checking for the source linedef's flags every time.
