Send a notification to a teacher if there are hours to approve, applications awaiting. Admins if there are Raise Applications or TA Training approval requests. - in bulk, once a week when more changes accumulated, link to appropriate web page. (using `@Scheduled`) * [x] Teachers when declarations aren't handled * List of courses/positions in one email * [x] Anyone that can edit payscale, when raise requests awaiting * [x] Anyone that can approve training, when training requests request awaiting