Processing translate names and groups

[arnaud-morvan]

Add a python tool function to generate a python file which calls QCoreApplication.translate with algorithm names and groups.
This script have to be run from QGIS console (import of processing so qgis python api may be on python path).

from processing.tools.translation import updateTranslations
updateTranslations()

pylupdate will push these strings in .ts file when running update_ts.sh.

Alter AlgorithmClassification to return translated names and groups for the toolbox.

For the moment, I hav'nt pushed the produced python file.

Need validation for translation context strings for names and groups.

[volaya]

Looks good, but don't forget that there is another toolbox in the modeler, were algorithms and groups should also be translated. You PR doesn't seems to address that.

[arnaud-morvan]

@volaya
Thanks for review

I've translated modeleur toolbox groups, for the names, it already use displayName() which return translated strings.
I've also added some comments in files and used "AlgorithmClassification" as context string for groups.
I've commited the python module containing translation strings (not pushed to transifex for now).
(commit amended, forced push)

[volaya]

Ok, this looks good to me. I will leave it to @alexbruy to confirm the merge, since he is the one that started all the Processing translation effort, and I do not know very well how the translation system works, but i think this is fine to merge.

Thanks for your work, Arnaud!

[m-kuhn]

When compiling latest master I get:

/dev/cpp/qgis/build/python/plugins/processing/stageinstall.cmake:12648: error: file COPY cannot find "/dev/cpp/qgis/QGIS/python/plugins/processing/algs/translations.py".

Is this related to this PR? Is this only a local issue and how can it be fixed?

[alexbruy]

@m-kuhn looks like related to this PR, but I can not reproduce it. Maybe local issue

[m-kuhn]

I realized that it is related to having WITH_STAGED_PLUGINS activated, but it no longer happens, so maybe only with a clean build dir?