Compare pep517 packaging: setuptools vs hatch

[sarnold]

• first commit is setuptools build backend with metadata in setup.cfg and configs in toml (uses setuptools-scm)
• second commit moves metadata to toml and build backend to hatch (uses hatch-vcs)
• second option includes (optional) hatch.toml environment config to run tests with coverage
• also includes simple os/python matrix CI workflow

Note the hatch config still builds fine the usual (non-deprecated) commands, eg, python -m build still works as expected.