I couldn't find the original depend.awk (which started out on vms) and
didn't feel like attempting to recreate it, so did this the old fashioned
way (grep,&c of src/*.c). I think that all of the various Makefiles need
one or more of these changes. Adding context.h to the hack.h dependencies
and emin.h to monst.{o|obj} are the most significant ones.
07f7384460