LMS-1468 Remove all comments created by push/pull

Summary of improvement suggestion

Allow users to delete all comments added to a document as part of the copy provisions (push/pull) feature in one step.

This could be done by giving all those comments some recognisable prefix and then deleting all comments containing that prefix

See original discussion in LMS-860 Feature logged .

Status	Feature logged
Lawmaker components affected	Comments, Editor, push/pull
Raised by organisation(s)	PCO
Planned version to be included in (if any)
Related development ticket(s)