Mark recent changes as reviewed

[martinszy]

Hi, we're having some moderators and it's being hard to keep track of what changes have been reviewed. Ideally, each change has a checkbox that can be ticked by a user that has the correct permission and this information is stored together with the change. If the change has been reviewed, then the next moderator can safely ignore that change and go on with the unchecked ones.

I guess this shouldn't be hard to implement and is quite convenient.

[mhl]

Nice idea - I've created a "recent-changes" label to group this with the other requests for improvements to the "Recent Changes" page

[mhl]

Especially since we're shortly going to add a page that just lists changes that are particularly worth reviewing (e.g. those from new users) I think this would be a good issue to work on. In the data model we will want a ChangeReviewed model with a ForeignKey to Person, a ForeignKey to Logged Action, a reviewer field (a ForeignKey to User) and possibly also an "outcome" field.

Making this a join table (i.e. with the three foreign keys) will mean that multiple people can review a single change, which seems desirable to me.

The "outcome" for the moment might just be "Looks fine" or "Fixed" (presumably when people see a change that's bad then they'll fix it immediately).

As with other moderation features, there should be a new group called "Trusted to review changes" which you have to be a member of in order to see the interface on /recent-changes for marking a change as reviewed.

We should have enough design time this week for @zarino or @wrightmartin to help with the design and usability of the /recent-changes page. There are lots of possibilities for making these page more usuable that would be worth considering at the same time, including some of these suggestions: https://github.com/mysociety/yournextrepresentative/labels/recent-changes )

As work on part of #140, we'll also add a page / feed for changes that might be suspect, and it would make sense to have the same interface for that. Since that's not done yet, however, let's just apply this to the /recent-changes/ page for the moment.

However, I think it's important to break this down into simple steps, starting with the additions to the data model.