Django-cked

- Add support Django 4.0

- Updated CKEditor to 4.17.1

- Updated elFinder to 2.0.9
- Refactor elFinder connector to Python 3.6+ and Django 2.2+
- Updated CKEditor to 4.16.0
- Changed default settings for CKEditor skin from "bootstrapck" to "moono-lisa"
- Drop older Django versions (<2.1) support
- Changed the default value of CKEDITOR_DEFAULT_OPTIONS from 'ru' to 'en'

- Added support Dajngo 1.9

- Updated CKEditor

- Fixed some bugs.
- Added support Python 2.7 + 3.4 and Django 1.7