[Distutils] [Catalog-sig] Prototype setuptools-specific PyPI index.

["Martin v. Löwis"]

> That's a secondary benefit. The main goal is to avoid the expense of
> that page for packages that aren't in PyPI, as some packages I use aren't.

I see. Shouldn't that be fixed by providing an option to setuptools
that avoids going to the index for missing packages?

Regards,
Martin