Textile

* Update supported Python versions to 3.8 - 3.12 (https://github.com/textile/python-textile/pull/83)
* Replace html5lib with nh3 for html sanitization
* General code cleanup
* Bugfixes:
* Wrong HTML output when "bc.." is the very last in the document (https://github.com/textile/python-textile/issues/81)
* Other:
* Use github actions instead of travis for automated testing

- Bugfixes:
- Support non-http schemas in url refs (75)
- pytest-runner is deprecated (77)
- other changes related to CI infrastructure

* Bugfixes:
* SyntaxWarnings with Python 3.8 (71)
* testsuite: internal error with coverage 5.0.X (72)
* DeprecationWarnings about invalid escape sequences (73)

* Drop support for Python 2, hence the version bump. Update list of PY3K versions to currently-supported versions. If you need to use textile on Python 2.7 or Python 3.3 or 3.4, please use textile Version 3.0.4.
* For use in PyPy environments, textile used to work well with the regex package. Lately, it's running into trouble. Please uninstall regex if this is the case for you.

* BUGFIX: Restricted mode strips out CSS attributes again.
* Update travis to more current versions and test against current Pillow version.

* BUGFIX: Improve handling code block following extended p block (63)