Infrastructure

Redmine 3.4 is out with a chunk of interesting new features
Let's arrange an upgrade time (~next week) with Florian and try it out

In the past, upgrades worked like a charm, and we have not many plugins, especially none that modify the database IIRC

Not urgent, as there are no security fixes in though

While we're at it, Florian would also like to search for plugins that

1. have thumbnail preview (unless that's part of the core already)
2. offer editing of issue author (to change notification paths)