Migrate metadata from setup.py to setup.cfg

[cclauss]

Done using https://pypi.org/project/setuptools-py2cfg plus manual modifications.

After this is reviewed and landed, a migration to pyproject.toml can be achieved using https://pypi.org/project/ini2toml or similar.

[coveralls]

Coverage decreased (-86.06%) to 0.0% when pulling 0f241bf on cclauss:patch-1 into 6c1e67e on PyCQA:master.

[atodorov]

Why is this change needed?

[cclauss]

https://setuptools.pypa.io/en/latest/userguide/quickstart.html#basic-use

Setuptools offers first class support for setup.py files as a configuration mechanism.
It is important to remember, however, that running this file as a script (e.g. python setup.py sdist) is strongly discouraged, and that the majority of the command line interfaces are (or will be) deprecated [ ... ]
We also recommend users expose as much as possible configuration in a more declarative way via the pyproject.toml or setup.cfg, and keep the setup.py minimal with only the dynamic parts (or even omit it completely if applicable).

https://blog.ganssle.io/articles/2021/10/setup-py-deprecated.html
https://thehackernews.com/2022/09/warning-pypi-feature-executes-code.html

[carlio]

I have been (manually) moving over to poetry so I will close this as basically done