v0.22.2

Packaging and citation metadata. No code changes from 0.22.0.

This supersedes 0.22.1, which was never published to PyPI: a git add -A in its
version bump swept in a scratch build directory named dist_0210/, so the
0.21.0 wheel and sdist (272 KB) ended up in the repository, in the v0.22.1 tag
and in the sdist built from it. .gitignore covered dist/ but not a
differently-named build directory; it is now dist*/.

Changed

• pyproject.toml's authors field said just Michael, which is what PyPI
  would have shown as the author. It now names K.-Michael Aye.

• New CITATION.cff, which drives GitHub's "Cite this repository" button, and
  new .zenodo.json, which overrides the creators Zenodo otherwise infers from
  the repository's contributor statistics. Both carry ORCID
  0000-0002-4088-1928 in the form each
  format requires: CFF takes the full https://orcid.org/ URL, Zenodo's API
  takes the bare identifier.

Fixed

• The repository no longer carries build artefacts, and dist*/ is ignored.