Merge pull request #281 from pryds/master

Updated Danish translation
wb_presets: nikon d3200 updated and expanded presets
(cherry picked from commit a3d1ce7a17d53d526edbbd91b5eefb76f9d9e6d0)
rawspeed: Sony SLT-A58 updated white and black levels
(cherry picked from commit cb4df09d96536dfc62e535a3438cc8d2e08b042c)
Merge branch 'master' of https://github.com/darktable-org/darktable
rawspeed: remove unused variable
(cherry picked from commit 14db78cb6fda8c3f8e351c8cbfbd068e1b338b5f)
wb_presets: Sony SLT-A58 (thanks to Flemming Christensen)
wb_presets: Sony SLT-A58 (fixed)
blending: fix recent warning message 'unknown blend mode 0'
Merge branch 'master' of ssh://github.com/darktable-org/darktable
Slightly change dt_develop_blend_params_is_all_zero

no need to keep iterating if we already know the answer
blending: partly revert commit 21a9f06732746023da827e8061afec2dbab9aa15 with a better solution
remove dt_film_import_blocking

it was lying about what it was doing, this does not change the fact that the lua API is not working like expected, but it works like it used to, so  fix in another commit

also fix DT_SIGNAL_FILMROLLS_IMPORTED not being triggered at the right time
lua : add film handling

darktable.films : pseudo table of films

film.id  : the film's id
film.path : the film's path
film.# : images belonging to that film

image.film : the associated film object
lua : new event post-import-film

trigered when a film has finished import.

one extra parameter : the film that was imported
lua : make database.import return usefull information

when imorting an image : the image that has been imported

when importing a directory : the film that is imported

note that the function returns immediately, so when importing a film, the object is correct but the images havn't been imorted yet

use the post-import-film event to find out when import is done
usermanual: some first steps towards 1.4

main changes: reorganize docs on darkroom with a large section to explain
general concepts; first documentation on drawn masks.

still a lot to do!
Merge branch 'master' of ssh://github.com/darktable-org/darktable
usermanual: a few more screenshots
usermanual: some additions
Allow blend modes to be translated differently