* Lazy lighting init, fixes, and optimizations.
All corners are now made when first needed (some edge cases due to sloth)
Makes set_light accept null for the l_color parameter.
Fixes set_opacity not update has_opaque_atom on the turf.
Performance optimization to the internal lighting application code.
* NONSENSICAL_VALUE
Makes lighting corner generation blazingly fast (jesus christ spawn)
Makes overlays be ignored by timestop.
Fixes smart_vis_update(). I'm honestly suprised it's broken-ness didn't
show up earlier.
This might fix the null.x shuttle runtime. Can't say for certain however.
