Slight adjustment to the 3.12 schedule

[Matthias Clasen <matthias clasen gmail com>]

Hey distributors,

writing to inform you that the GNOME release team is pondering moving the date for 3.12.0 out by approximately a week, to align the schedule with the Wayland release plans (a 1.4.91 release including all the xdg-shell API we need is planned for April 1). The latter 3.11.x milestones would be shifted as well, to avoid lengthening the freeze period unnecessarily.

If this would throw your own schedule into major disarray, please speak up now.

With my Fedora contributor hat on, I can state that this will not cause problems for Fedora, since the f21 schedule is going to be longer than usual, anyway.

Thanks, Matthias