- allows ACE tracers to function properly at night
- all tracer rvmat's values have been changed to be closer or the same
as vanilla tracer rvmat values for the same tracer colour
- ace_shell_tracer_red is now a copy of ace_shell_tracer_yellow, but
using the red texture and rvmat.
This is because it had a completely different model then the other
ace_shell_tracer_xx models that was large, fuzzy, and translucent. it
made red tank tracers look like a big red cloud flying through the air.
* the new values for the rvmat's aren't perfect, but they work I will
probably tweak and test a little more
