Wagtail-rangefilter

- Fixed DateTimeRangeFilter for django-admin-rangefilter >= 0.12.
- Changed required django-admin-rangefilter to 0.12 and above.
- Adapted tests against Wagtail >= 6.0 due to removed `wagtail.contrib.modeladmin`
- Added tests against Wagtail 5.1, 5.2 (by lparsons396, katdom13)
- Drop tests for Wagtail 4.2, 5.0 and Django 4.1 as they have reached EOL (katdom13, th3hamm0r)

Added

- Added support for Wagtail 5.0, Django 4.2, and Python 3.11 (by katdom13)

Removed

- Removed support for Wagtail < 4.1, Django 4.0, and Python 3.7 (by katdom13)

- Improved buttons (1) by kevinhowbrook
- Improved testing and docs

Initial release