[gtk] (4 commits) Non-fast-forward update to branch wip/otte/listview

[Benjamin Otte <otte src gnome org>]

The branch 'wip/otte/listview' 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:

  55c188d... listview: Implement ::section-factory property
  a5ff901... gridview: Add support for sections
  bc11760... demo: Add a listview sections demo

Commits added to the branch:

  857478b... listview: Implement ::section-factory property
  2f9bb06... listview: Split out a function
  76ab29e... gridview: Add support for sections
  36c7b2f... demo: Add a listview sections demo