Activate GUI for watermark layout.

It is now possible to layout properly a watermark whose scale is
computed based on the larger or smaller border. This make it possible
to use a watermark inside a style an apply it into images in portrait
and landscape mode with proper layout.
white balance: make it relative to daylight balance

assuming that has been created wrt CIE daylight.

the end result is somewhat similar to ufraw, numbers vary wildly
but in principle it's relative to something constant and not to
camera white balance anymore.

also removed second temperature slider.
bauhaus: also reset to default on double click if -1 entry was selected.
Merge branch 'watermark-layout-options'

* watermark-layout-options:
  Activate GUI for watermark layout.
Update french translation.
whitebalance: default temperature is daylight wb
allow zoom under the "fit to screen" limit
smaller zoom steps under "fit to screen"
new module colormapping as a replacement for colortransfer
deprecate colortransfer module
Merge branch 'master' into colormapping
Merge pull request #208 from darktable-org/gnd_fix

Gnd fix
borders.c: fix typo portait
colorspaces: (again) this should be fine with Adobe's trademarks as well
darktableconfig: bring lcms2 description in line with recent changes
splittoning: more bauhaus love
[l10n] Swedish update: 7 fuzzies, 1 new string.
Fix some french translations and add some new ones.
splittoning: sync all sliders correctly
purge images: tony arnold's version.