Provide utility scripts to manipulate / explore backups

[delroth]

Reading backups is kind of inconvenient right now, requiring manual setting of BORG_RSH + copy-pasting the appropriate passphrase for the host from secrets. Could do something like: eval $(backup-config $mach) to automatically provide the right environment.

[delroth]

Once moved to proper secret management I should be able to just use the default provided borg-job-default script -- right now it doesn't really work because my Borg setup relies on copying the private SSH key from the store.