[gnome-control-center] (4 commits) Non-fast-forward update to branch issue12

[Georges Basile Stavracas Neto <gbsneto src gnome org>]

The branch 'issue12' was changed in a way that was not a fast-forward update.
NOTE: This may cause problems for people pulling from the branch. For more information,
please see:

 https://wiki.gnome.org/Git/Help/NonFastForward

Commits removed from the branch:

  0b6334d... display: Early return in monitor_labeler_show() if no outpu

Commits added to the branch:

  3117e2d... network: Remove nagging code which removed from libnma (*)
  72ef675... network: Fix warning about missing cast to GtkWidget* (*)
  729db87... network: Remove dead code trying to use NMConnection as NMA (*)
  ca9228b... display: Early return in monitor_labeler_show() if no outpu

(*) This commit already existed in another branch; no separate mail sent