Add rendering support for CustomBoolean5-7

[zrksyd]

Only allow material animations if CustomBoolean5/ CustomBoolean6 / CustomBoolean7 is on. Maybe add a setting in render settings to disable this similar to disabling yellow checkerboard rendering.

[ScanMountGoat]

Adding rendering support for booleans should be pretty doable. There are other animated material properties that don't depend on booleans to work properly. I won't make this toggleable from settings since that complicates the shaders too much. If documenting the parameters in the matl editor isn't good enough, I'll reassess later. Checkerboard rendering was only toggleable in Cross Mod because it had some false positives where it rendered a checkerboard when it shouldn't.