* Add splitter in order to hide the details table.
* Add a toolbar to the Details Dialog window to allow for better image
comparisons: zoom in/out, swap pixmaps in place, best-fit-to-viewport.
Scrollbars and viewports are synchronized.
- Format all files with black
- Update tox.ini flake8 arguments to be compatible
- Add black to requirements-extra.txt
- Reduce ignored flake8 rules and fix a few violations