first, rough version

@carlaschroder lots to do still - I'd like feedback especially from Jennifer, but also @dragotin @karlitschek @danimo @LukasReschke @PVince81 and others ;-)

Mostly on the gaps and the questions in there...
My rule was usually:
1) If the ticket is for a version before the current one: ask the person to try again with the last version.
2) If the ticket is older than 2 months: close directly and state "feel free to reopen if you still see the issue with version {current_version}"
3) If the ticket is more recent, keep it open.
4) If after many weeks there was no answer, close the ticket.

But these might be a bit too complex to write down. Maybe we can simply set a timeout of a month: no feedback from reporter after a month => close. What do you think ?