[Distutils] setuptools and Mac OS X minor updates

[Kevin Dangoor]

This morning, I updated to Mac OS 10.4.2 and then discovered that one
of my eggs could no longer be found. Rebuilding the egg gave me the
answer: Darwin had bumped from 8.1 to 8.2.

My guess is that an egg built under Mac OS 10.4.2 will work just fine
on a 10.4.1 Mac. It would be a drag to have a separate egg for each
minor revision of the OS.

Should this be done differently? I seem to remember an option for
setting the platform, but I wouldn't want to do something that would
break how easy_install does things.

Kevin