add archive-prune feature
It should be possible to define pruning rules in grob config. Rules shall be specified on per drive or will be inherited from above.
The following numbers of archives to keep can be specified:
- hourly
- daily
- weekly
- monthly
- yearly
Grob shall only use that settings when beeing run with grob archive-prune
.
grob prune will run borg prune, which will do the job and it will use --glob-archives
to make sure it works only on one drive at once
Edited by Heinz Deinhart