[Catalog-sig] Changing cheeseshop.python.org to pypi.python.org

["Martin v. Löwis"]

After some discussion, it seems that nobody really likes
the name "cheeseshop" for the Python Package Index,
and some people seem to actively hate it.

So I'm going to change the name (again/back): the software
will call itself "Python Package Index", abbreviated as
pypi (PyPI where case matters). The machine address
cheeseshop.python.org will continue to work for a
foreseeable future, but will not be actively advertised.

Regards,
Martin