Having the runway lights "pop" in at a specific range is not 100% realistic.

Having the runway lights "pop" in at a specific range is not 100% realistic.
I have updated the lighting code to use fog to try to fade the runway lights
in smoothly, but still keep them from being visible until you are about 7-10
miles out, and then only have them be very faint at first.  I think what I
have is a bit nicer than before since it completely avoids the "popping" effect,
but I've very open to tweaking the actual ranges based on people's real
world experiences.