Translation for templates and forms

I found two `` tags in the templates, but they were not done extensively. I was about to undertake the task of tagging more of these texts with `{% trans%}` tags, as well as using `ugettext_lazy` in python files. I am thinking about using `_` notation:

from django.utils.translation import ugettext_lazy as _

I was wondering how the maintainer wants to handle the resulting .po files. They will diverge from the json files that Numbas compiler generates. If kept separate, it will result in a diverged effort in translating on poeditor.com; combining them could be a maintenance hassle and an extra dependency. Two repositories are already coupled, and perhaps guidance on how de-coupled they need to be would be helpful.

The primary motivation behind the effort is how I disagree with the term "Group," "Exam," "Question." I want to use "Section," "Deck," and "Slide" instead. I think they are more generic. For URL endpoints, [LocalMiddleware](https://docs.djangoproject.com/en/dev/topics/i18n/translation/#url-internationalization) can be used, but this is not a priority.

If there are other details I should read over, let me know! I will catch up with the documentation soon.

Start by reviewing the existing tags, Python files using ugettext_lazy, and the Django URL internationalization documentation. Clarify how .po files should relate to the JSON files generated by the Numbas compiler and whether the repositories should remain coupled. Done requires an agreed scope and a consistent translation workflow for the proposed terminology.

Written by the indexing model from the issue text.