Add WolfET Decal Projector code

[zturtleman]

Add WolfET Decal Projector code

[zturtleman]

Add the WolfET Dynamic Light code (issue #2) first as decal code will be easier to port after that.

[Zombrero]

Can you make decals also shown on trains (e.g.: map railgun) and also on players?

[zturtleman]

I'm not very familiar with ET, by trains do you mean the yellow vehicles (called tugs in limbo menu) on map railgun? In ET bullet decals seem to show fine on the second tug, but only sometimes show on a few parts the first tug. This seems odd and should be looked into...

Projecting decals onto non-world surfaces (such as player models) seems like a good idea.

[zturtleman]

I plan to extend MarkFragments to work to brush entities instead of adding ET Decal API. Closing issue.