*****
Bugfix release.
* Fix for newer Docutils change in node attributes (MB).
* Test fixes for newer Sphinx, Notebook, nbconvert (Lumir Balhar, MB).
* Fix escapes in not-raw strings (Jerry James).
* Fix import of Sequence for newer Python (Jerry James).
* Update versioneer (MB).
* Tox / Github actions for testing (Lumir Balhar)
*****