Gtk+ merges

[Alexander Larsson <alexl redhat com>]

I see some commits in git master, like
4134c346f9e68367e515345c0ded07aa2b857a1a that looks kinda weird.
Federico, did you really mean to merge all of the stable branch into the
unstable branch, or did you just want to cherry-pick that particular
commit? (To see how it looks weird, check it out with gitk on master)

In general, maybe we should come up with a standard workflow for
applying things to the stable and unstable branch.

I don't think merging the stable branch ever makes sense, we don't want
to merge e.g. a version bump in the stable branch to the unstable. I
think the best approach is to commit fixes to master, then cherry-pick
them to the stable branch.