This will make a number of things easier in the future, as well as (finally!)
avoiding the Id-smashing problem which has plagued developers for so long.
Boy, I'm glad we're not using sup anymore. This update would have been
insane otherwise.
type instead of int all over the place. (Cosmetic, enhances
debugging.)
Point out that a date specification _must_ follow the time of day
spec, in the man page. This clarifies the last point PR # of bin/483:
"at doesn't seem to ..." (the remainder has already been fixed with
version 1.3 of parsetime.c).
