[Distutils] Name the software! Package quality tester.

[Carl Meyer]

FWIW, when I've been writing docs or answering packaging questions and
trying to use the approved, unambiguous terminology, using "project" for
"thing with a PyPI page" has never been a problem; I've had much more
difficulty in using "distribution" as the term for "a zipfile or tarball
or egg that you download" (also a "package" in colloquial usage). I
always have to awkwardly qualify it with "distribution tarball" or
"project distribution" due to the conflict with Linux distributions.

Carl