Clean up QMLBench database and dashboard

The QMLBench dashboard is defaulting to an obsolete configuration. The dashboard can be updated to show the current configs as default (just select the correct variables and then save the dashboard with the "Include current variables" checkbox checked).

At the same time, it would be useful to clean up the database and archive the outdated platforms/branches that are not really useful in day-to-day operations. jimis should be able to provide some guidance on how to archive a database. Following archiving actions, the archived points from the current database should be dropped.