Added COLOR!!  But really, instead of the way I did it, which was to
use the actual int values, we should change the def.h to not use defines,
as that throws very weird errors on compilation if included in the terrain_defs,
and the errors are within SDL itself (the define for, say, yellow, is somewhere
in the SDL library, so it throws an error because it thinks the yellow SDL is trying
to use is just an int).  So, we should change the defines to const ints instead, or change
the names in the defines (starting each one with a capital letter would do it).

Either way.

Then we need to go back into the terrain_defs and implement it there.