Tweaks for the new DX9 renderer

I removed most of the Z-BIAS / DEPTHBIAS hacks except for those cases in which they definitely were required for my system in DX9 (incorrect ordered if not applied)

Fixed issues with Dx9:
1) Z-Fighting of room wireframe (bloody hack to close gaps on edges) with actualy room ("black lines" on some walls/floors should be gone)
2) Z-ordering issue with objects<->room (the depthbias hack moved them too much off their real position)