Extend revisions to include lists, tags and settings

[Kovah]

• venturecraft/revisionable is replaced by owen-it/laravel-auditing
• old revisions are migrated to the new audits
• lists and tags are now monitored, the logs can be found on the detail page of the corresponding entity
• system settings are now monitored, the logs can be found on the new "audit logs" page, available only to administrators
• users are now monitored, the logs can be found on the new "audit logs" page