[FEATURE REQUEST] Support for Spoolman

[Low-Frequency]

Auto detect Spoolman installations and add the database to the files to be backed up.

Use this script as reference for backups.

With this the backup and restore functions have to be redesigned. Make sure to ensure compatibility with v2 functionality to not break existing installations.

[Low-Frequency]

Spoolman support is implemented in branch spoolman. Release after updating the documentation.