Re-schedule tasks when restarting queue

[wdoekes]

When restarting the PlanB (celery) Queue, all tasks are dropped:

Sep 14 10:35:19 osso-backup-dr systemd[1]: planb-queue.service: Succeeded.
Sep 14 10:35:19 osso-backup-dr systemd[1]: Stopped PlanB Queue server.
Sep 14 10:35:19 osso-backup-dr systemd[1]: Starting PlanB Queue server...
Sep 14 10:35:20 osso-backup-dr planb[933328]: Dropped 2 jobs from DB queue
Sep 14 10:35:20 osso-backup-dr systemd[1]: Started PlanB Queue server.

Expected/wanted behaviour:

• drop redis stuff
• drop is_running
• resume work were we left off: i.e. re-enqueue all jobs (possibly starting with is_running first)

[wdoekes]

Whatever.