Ptulsconv

I think the tag on v1.0.2 was pointing to an incomplete revision, this is a good one.

* Some fixes to silence test warnings.
* Updates to the test and deploy workflows.

This is mostly to test my new Pypi upload workflow, though there is one new feature:

* Version and copyright message are displayed with every run now, including with `-h`, and not just when a document is generated.

Seems like the time! I've been using this really reliably on multiple projects, I have ideas for new features but I think this is a good product.

* Added Python 3.10 to support and test lists

- Fixed README to reflect current operation
- Improved continuous integration
- Added Python 3.9 support