String change in gnome-desktop

[Federico Mena Quintero <federico novell com>]

Hi, translators,

I committed a change to
gnome-desktop/libgnome-desktop/gnome-rr-labeler.c.  It has a new string
"Mirror Screens".  This should already be translated in
gnome-control-center; you can steal the translation from there :)

Thanks,

  Federico