Rename anonymisation step

[marksteward]

The anonymisation step is also an initial quality screening check. Make this clear in the UI, replace things like Anon-blocked, and add some guidance to cfp-review/anonymisation. Make sure the CfP guidance doc includes this information.

[Jonty]

Context so we don't forget: The current issue is that the anonymisers will anonymise things and put them into review regardless of the proposal actually being good enough for someone to review.

They should be bouncing things back to submitters if the submission isn't good enough, ideally with feedback on what needs changing. This should be happening as soon as possible after submission to ensure we don't leave people hanging.

Related issue: Email reminders for proposers who have had their submission put back into the edit state as it's not good enough: #1791