TODO
- [ ] Delay task (Celery?)
- [ ] Store the image in a subfolder unique to the edition, to make cleaning up the image easy
- [ ] Clean up the image before replacing it
- [ ] Ensure that the image will be cleaned when the edition is deleted ??
- [ ] Use instance custom colors?
- [ ] Use book cover color base?
- Add Github Action.
- Update .gitignore.
- Add .stylelintignore for vendor related files.
- Fix format.css to match rules (includes hacks with @todo).