* Add ability to mark moderation reports as 'handled' or 'rejected'.
* Automatically mark reports as handled when the comment or forum post
is deleted.
* Send a dmail to the reporter when their report is handled.
* Don't show the report notice on comments or forum posts when all
reports against it have been handled or rejected.
* Add a fix script to mark all existing reports for deleted comments,
forum posts, or dmails as handled.
