Comment 2 for bug 675504

After looking more closely at django-gatekeeper I think we can use it - see the linked branch.

It has the following differences from our original model:
 1) moderation objects are *always* created when a review is created - which makes sense when we use the automoderation (blacklisted words or even askimet).
 2) When flagging a review, it doesn't have separate fields for the flag category (eg. "SPAM") and the textual reason entered by the flagger ("I consider the links here spam."). So you'll see I'm currently storing both in the moderation_reason field as "Flagged by userjoe for 'SPAM': I consider the links here spam.". I think this is OK as long as we're intending the category to be something helping the flagger - ie. we won't be able to sort by flag category etc.

If these differences are unwanted, then we can create our own moderation app (just start by moving the ModerationRequest object out and begin building in the features of django-moderation/django-gatekeeper that we want).