Apologies

* Refactor the run script and pre-commit hooks to reduce duplication.
* Rework the GitHub Actions build process to pull out shared code.

* Upgrade to Poetry v1.2.0 and make related build process changes.
* Upgrade to Pylint v2.15.0 and make related changes to configuration
* Fix Pylint's configured class-attribute-naming-style to be snake_case.
* Adjust Black configuration to target Python 3.7, 3.8, 3.9, and 3.10.
* Add dependency caching to GitHub Actions workflow.
* Fix the GitHub Actions matrix build to properly target Windows and MacOS.
* Make improvements to the curses-based demo and test it in the tox suite.
* Address annoying PyUnresolvedReferences warnings in PyCharm.

* Modernize usage of attrs library.

* Adjust the pyproject.toml include directive to limit what goes into wheel.
* Remove the Safety scanner from the pre-commit hooks and GitHub action.

* Adjust dependencies and build process to support Python 3.10.
* Run test suite with python-testdox for more verbose output.

* Standardize the format of the Apache v2 statement in LICENSE.