[gimp] (10 commits) Non-fast-forward update to branch wip/Jehan/incremental-win-installer-improvements

[Jehan <jehanp src gnome org>]

The branch 'wip/Jehan/incremental-win-installer-improvements' 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:

  2918438... build: separate debug symbols from binaries in the Windows 
  326ad37... build: create installer with debug symbols, Python and Lua 
  c489870... build: add a test to check the Windows installer languages.
  4a973e2... meson: -Dwindows-installer also works on Windows.
  f010ce3... build: job win-installer-nightly should return failure appr
  1acaf01... build: extensions are gimp32/64 specific.
  e1efcaf... Test: drop Lua temporarily.
  2b3246b... Test: install lua51 and lua51-lgi.
  275aa47... WIP.
  2034451... More WIP!
  860350b... Disable LUA again.
  523e8cf... Plop.
  fad74c1... Wrong prefix!
  76fd36e... Argh.

Commits added to the branch:

  016948c... plug-ins: load 16-bit per sample SGI images as 16 bit integ (*)
  5861ee8... build: separate debug symbols from binaries in the Windows 
  1c018aa... build: create installer with debug symbols and Python suppo
  9efe8a1... build: add a test to check the Windows installer languages.
  572d716... meson: -Dwindows-installer also works on Windows.
  7b32aa4... build: job win-installer-nightly should return failure appr
  7e2522e... build: extensions are gimp32/64 specific.
  f1a861d... build: fix Python support in Windows installer.
  c0dc10c... Test: install lua51 and lua51-lgi.
  8869112... Add GObject Introspection libs.

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