[Feature] Limit pending edits per user

[StashManRon]

(Copy of issue formerly known as #782 - Github have shadow banned me ....)

Is your feature request related to a problem? Please describe.

Currently users can submit an unlimited amount of concurrent edits regardless of experience/quality of submissions

Describe the solution you'd like

A maximum limit which is definable by admins. For further complication the limits could be definable by role and to further complicate, those with few successful edits only get say 5 pending edits and as they have more submissions successfully add then they can have more concurrent pending edits ...

Describe alternatives you've considered

Leaving it as is but in some cases this means the edit queues can get spammed/flooded