[gtk] (7 commits) Non-fast-forward update to branch gamma-shenanigans

[Matthias Clasen <matthiasc src gnome org>]

The branch 'gamma-shenanigans' 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:

  1c90cf2... Support 16bit textures
  7ff8404... Add private api to download textures
  068499f... Support loading and saving 16bit pngs
  9dc0cae... Support 16-bit floating point textures
  120b671... Support 32-bit floating point textures
  ccca426... Add gdk_texture_save_to_file
  8ab45de... Support loading and saving float textures

Commits added to the branch:

  8b14c4b... Support 16bit textures
  5b1d861... Add private api to download textures
  2cdc20d... Support loading and saving 16bit pngs
  85c1da6... Support 16-bit floating point textures
  eaf350c... Support 32-bit floating point textures
  c3de06d... Add gdk_texture_save_to_file
  8d6ef14... Support loading and saving float textures