Rudder

1. copy from ruddersysevents to archivedreports
2. delete from ruddersysevents
3. vaccumm

If the webapp is stopped between 1 and 2, we have the archive in an invalid state, causing it to fail later as it tries to insert already existing entries into the archivedruddersysevents.

In fact, we want to be able to have the archived execution reports on an other DB, so we don't want to add transaction, but be smart about how we handle already migrated reports.