Add support for flip module in lightroom import.
masks and blending: revamped unified GUI
Merge branch 'master' into blendmasks
masks and blending: add mask combination options: substractive/additive, normal/inversed
Merge branch 'master' into blendmasks
masks and blending: some wording changes
masks and blending: some ui fixes
Merge branch 'master' into blendmasks
masks and blending: fix some logical flaws
Merge branch 'master' into blendmasks
masks and blending: minor gui changes
masks and blending: add functionality for deprecated blend modes

* make blend modes 'inverse' deprecated as masks can now be inverted
* introduce new blend mode 'difference' (better working in Lab) and make
  old one deprecated
Add a strength modifier to the colorzone module.

This can be used to adjust globally (that is for the LCh channels) the
actual strength of the effect.
masks and blending: a few wording changes in UI
Add new Lensfun geometry transformations introduced in 0.2.7. This fixes #9133.
Merge branch 'master' of github.com:darktable-org/darktable
lens.c: don't forget our ban on caps
masks and blending: fix bug in legacy parameter handling
Merge branch 'lr-import-orientation'

* lr-import-orientation:
  Add support for flip module in lightroom import.
usermanual: no whitespace in id tags