Change shake times to even number, so the dialog can return to its original position.

Avoid deprecated gdk_window_set_background functions

Which are completely broken in GTK+ 3.22.

Update mate-screensaver NEWS to use consistent, project wide, markdown-like formatting. This will make generating release announcements easier.

and require libmatekbd and libmate-desktop >= 1.17

In some systems the gdm binary is actually called "gdm-binary", so we
need to check for that too.

fixes https://github.com/mate-desktop/mate-screensaver/issues/104

If the screensaver is already active without a lock, and it got a
request to lock, it would bail out without switching to a locked
state.

https://bugzilla.gnome.org/show_bug.cgi?id=668967

commit adfc2809 changed the drawing area associated with each
monitors screensaver window to get realized early.

That change is seemingly causing problems for users.

This commit stops preemptively realizing the drawing areas, and
instead makes the background color settings get applied reactively
in response to realization.

http://bugzilla.gnome.org/show_bug.cgi?id=679441