Add French screenshots in the French version of usermanual (till 3.4.2.2)
*.png et *_fr.png = French version
*_en.png = English version
Merge branch 'master' of https://github.com/darktable-org/darktable
add file *_en.png and *_fr.png
Delete all French screenshots named *_fr.png in the usermanual. French screenshots are named *png.
French screenshots are introduced till effects group (not included)
Add French screenshots in Chapters 1, 2 and 3
Add all the frecnh screenshots in the usermanual
Merge branch 'master' of https://github.com/darktable-org/darktable
Update French usermanual
Merge branch 'master' of https://github.com/darktable-org/darktable
Update French usermanual after a git pull upstream master
Merge branch 'master' of https://github.com/darktable-org/darktable
Update French translation of the usermanual after a git pull upstream master
Update usermanual after git pull upstreram master
Change some images after a few further fixes for #10175
Add French screenshots for defringe, rotate pixels an scaling pixels
Merge branch 'master' of https://github.com/darktable-org/darktable
fix libsecret detection on OS X
correctly check for Xrandr, fixes build on OS X (though cmstest there is pretty useless)
Merge pull request #727 from parafin/macosx

various cmake fixes for OS X, tested by LebedevRI on Debian SID.
usermanual: proofreading thanks to David Vincent-Jones