Make surface props 3 & 4 work for traces
* for 4 way blend shader. Also removed some unnecessary, non functional changes about surface prop 5/FDispCollTreeParams/SurfacePropAlphaFilter
Minor compile warning fixes
prop_exploding_barrel placeholder entity (CS:GO danger zone map)
Allow mesh.TexCoord to only accept 1 tex coord
So texcoord1 is mandatory, the other 3 are optional and use appropriate TexCoord4f/TexCoord3f/TexCoord2f methods internally
End current Lua mesh (if there is one) on Lua error
* This helps prevent the game from exploding into a million pieces on Lua error when generating meshes via the mesh library.
Adjust Lightmapped_4WayBlend $seamless_scale warning
* Do not complain about $DetailBlendMode with $seamless_scale without detail texture even being set. Also reset the detail texture if given bad blend mode so that it's renders better in the flashlight pass