Blender Git Loki

I switched the linux side of things to use pkg-config for
OpenEXR, and I switched all of the other platforms back to
no ThreadLib. I really was trying to make this easier for people not
harder, and I'm afraid I failed. Hopefully this clears things up for
people and everyone will switch to using the Makefiles. ;)

If your having problems you should be able to just add the IlmThread lib
back into your NAN_OPENEXR_LIBS inside of your user-def.mk and be good to
go. let me know if you have problems with it.

Kent