Results 2 issues of Fysac

I'm getting these errors that are blocking backups from happening; something to do with a stale lock not getting cleaned up? ``` backups | 2021-12-31T17:47:58+0000 ERROR unable to create lock...

It would be nice for `POST_BACKUP_SCRIPT` to be able to detect when a backup failed, so that it can send out a notification in case of an error (e.g., an...