Feat: settime chat command

[ToeKneeRED]

It is about the same if not the same as the previous PR for it from cosi. Adds a /settime chat command that can be used on any server that is not public.

Ideally, there would be some feedback from the server that it succeeded or failed besides the time change (e.g. a localized chat message, but that turned out to be too complex for me).