[gtk] (9 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:

  ba52ea7... Add private api to download textures
  f081a5f... Support loading and saving 16bit pngs
  4c729c5... Support 16-bit floating point textures
  e643e4b... Support 32-bit floating point textures
  e9bee9a... Add gdk_texture_save_to_file
  ed49737... Support loading and saving float textures
  7915f33... Redo the conversion setup for memory formats
  6b10dc5... Allow conversion to hdr formats
  fe03bfa... Add gdk_texture_download_float

Commits added to the branch:

  af08757... Add private api to download textures
  2ff5ae4... Support loading and saving 16bit pngs
  1708a1d... Support 16-bit floating point textures
  e96e493... Support 32-bit floating point textures
  1203922... Add gdk_texture_save_to_file
  29b9eb8... Support loading and saving float textures
  8d6353c... Redo the conversion setup for memory formats
  ff55331... Allow conversion to hdr formats
  9f055fe... Add gdk_texture_download_float