Django-comments-xtd

* Fixes issue related to missing frontend files within the package distribution.

* Fixes [issue 407](<https://github.com/danirus/django-comments-xtd/issues/377): `ReadCommentSerializer.get_submit_date` does not properly use `DATETIME_FORMAT` setting.
* Adds the new setting `COMMENTS_XTD_API_DATETIME_FORMAT`.

* Adds support for Django 5.0.

* Updates ReactJS plugin. It has been rewritten to use React Hooks.
* Add tests to cover over 90% functionality of the JavaScript plugin.
* Replaces Webpack with Rollup to create the JavaScript bundle.
* Updates the UI to use Bootstrap 5.3.0.
* Updates the demo sites to Bootstrap 5.3.0.
* Extends python tests to Django 4.2 using Python 3.11.
* Updates the docs.

* Extends compatibility to django-rest-framework v3.14.

* Fixes [issue 377](https://github.com/danirus/django-comments-xtd/issues/377): content_object is missing in followup notification. View `notify_comment_followers` has been updated to include `content_object` in the context of templates it uses: `email_followup_comment.txt` and `email_followup_comment.html`.
* Update translation files to the latest strings found in templates. Next step is to include appropriate translations. See [PR 379](https://github.com/danirus/django-comments-xtd/pull/379).