Add scripts to restore and verify backups

[nalt]

Restoring an incremental backup requires multiple commands, so it would really be helpful to have a script to automate (and test) restoring.

To that end, the dependancy qpress should also be included.

Then it should also be straight-forward to run MySQL/MariaDB server to actually test the restored data. Because a backup is only worth it if it actually works...

[woolfg]

Hey @nalt, thanks for the proposal. I fully agree, would be nice to have it automated as well. Do you have time to contribute it? I could also support if needed. cheers, Wolfgang