[Mailman-Developers] Common use case archiving via configuration

[Stephen J. Turnbull]

Andrew Stuart writes:

 > What does "batteries included" mean in this context?

That you shouldn't need to fetch the archivers from a separate archive
or repo to configure them.  Sure, you *could* register them as plugins
and have a button to fetch them from PyPI (or just do it if the user
selects one, but I don't see a huge benefit to that practice in this
case.

Thus I prefer a contrib directory or subtree to the repo proposal.