Djangocms-blog

* Fix channels support
* Avoid admin exception for related posts when config is None
* Fix error when overriding templates folder

* Add support for django 3.0
* Add BlogAuthorPostsListPlugin to show posts per author
* Add experimental support for django-app-enabler
* Remove cmsplugin_filer from installation docs
* Set minimum django-parler version to 2.0
* Reduce the maximum length of slug fields to 752 characters
* Fix duplicated authors in BlogAuthorPostsPlugin
* Fix to respect current locale for category names
* Improve documentation for meta tags

* Add support for django CMS 3.7
* Add support for Python 3.7
* Add image size meta for Facebook
* Add support for django-parler >= 2
* Move to django-app-helper
* Drop support for Django < 1.11
* Drop support for django CMS < 3.5
* Drop older compatibilities

* Use menu_empty_categories config for BlogCategoryPlugin
* Purge menu cache when deleting a BlogConfig

* Fixed allow_unicode kwarg for AutoSlugField
* Fixed sphinx conf isort
* Set category as requested or not depending on the permalink setting

* Fixed issue with thumbnails not being preserved in admin form
* Pinned django-taggit version