[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:

  a262491... Support 16-bit floating point textures
  1fd72df... Support 32-bit floating point textures
  a4a2318... Add gdk_texture_save_to_file
  50c05d0... Support loading and saving float textures
  11dc025... Redo the conversion setup for memory formats
  ceb3b7a... Allow conversion to hdr formats
  7bc268c... Add gdk_texture_download_float

Commits added to the branch:

  e564c96... Support 16-bit floating point textures
  338471d... Support 32-bit floating point textures
  eb4cd15... Add gdk_texture_save_to_file
  b566d3d... Support loading and saving float textures
  08ad49d... Redo the conversion setup for memory formats
  8e443b9... Allow conversion to hdr formats
  c33a917... Add gdk_texture_download_float