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* Make sure comment moderation is always active.
* Added a "default moderator" for the models that are not registered via ``moderate_model()``.
* The default moderator is configurable via ``FLUENT_COMMENTS_DEFAULT_MODERATOR``.
* Spam filtering works, but "auto close/moderate after" support needs a registration via ``moderate_model()``.
* Added simple captcha support.
* Added "no captcha" reCAPTCHA2 support.
* Add new default ``FLUENT_COMMENTS_AKISMET_ACTION=auto`` option that
completely discards comments when Akismet classifies as definitive spam.
* Fixed using ``force_text()`` to generate the content object title for email.
* Fixed showing HTML in the comments admin.
* Fixed showing the preview multiple times for threaded comments.
* Included ``form.is_preview`` flag.