[Releasing] [IMPORTANT] staging in qt dev branches temporarily disabled

[Oswald Buddenhagen]

moin,

empirical evidence shows that People™ don't read announcments, and
consequently are still staging changes meant for 5.1 (i.e., bugfixes to
new functionality) to dev. these changes would miss 5.1, or need to be
cherry-picked, both of which are bad.

consequently i have temporarily "locked down" the relevant branches, so
really *everyone* gets it (i.e., is forced to ask wtf is going on).

unfortunately this also prevents staging changes which are legitimately
meant for dev.
the solution/workaround is simple: just add me or Sergio Ahumada to the
reviewers and ask for staging. i don't think this will be a real
bottleneck, but in case it turns out to be one, we can quickly create a
new group with people who are confirmed to be well-informed about the
state of affairs.

the "lock" can be removed on friday evening, i think. at least i hope
all integrations are done and everyone got that by this time.

sorry for the inconvenience.
hack on!