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...
Never assign anything as it feels rude to some people. Do mention people if you know who takes care of that part usually (ex: @schiesbn for encryption, @blizzz for LDAP, me for quota stuff, etc)