[retro-gtk] (16 commits) Non-fast-forward update to branch mkenums

[Adrien Plazas <aplazas src gnome org>]

The branch 'mkenums' 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:

  f931d1b... Build enum types with mk-enums
  e296cd6... pixel-format: Don't give it a GType
  24c4ac5... Drop custom enum GType funcs in favor of mk-enum

Commits added to the branch:

  9d3b599... Make the D-Bus API clearly private (*)
  8b3c93e... pixdata: Fix the doc of retro_pixdata_new() (*)
  b4b6d39... version: Give the doc section a better name and title (*)
  1bbb31d... log: Link to the signal in the retro_g_log() doc (*)
  87cec13... pixdata: Document the aspect ratio in retro_pixdata_to_pixb (*)
  9d3b4df... input: Fix %self for @self in doc (*)
  0c333d7... controller: Document RetroControllerInterface (*)
  e137760... Give basic documentation to public sections (*)
  4ac07d6... cairo-display: Give it some private section documentation (*)
  a2ebdff... gl-display: Give it some private section documentation (*)
  9872dcf... Allow building and installing the reference manual (*)
  71f006d... ci: Build and publish the reference manual (*)
  0620c98... Add HACKING.md (*)
  15ee543... Build enum types with mk-enums
  2889b1a... pixel-format: Don't give it a GType
  a701751... Drop custom enum GType funcs in favor of mk-enum

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