WARNING
**Breaking change:** Starting with version the 2.0.0 the category slugs are unique.
While this brings big advantage for simplified category addressing, it can break projects that are containing categories with duplicated slugs.
If your database contains colliding slugs, they will be automatically renamed by the migration.
Three categories with slugs ``foo`` will be renamed to ``foo``, ``foo-1``, ``foo-2``.
If this causes problems in your project, you can rename the categories yourself before running the migration.
- Django 2.1 is no longer supported