docs: add documentation about internationalization from a user perspective While there is already documentation about creating and updating translations (developer perspective), there was nothing for the user/admin of Kallithea. Since the handling in TurboGears2 is different, this is a good time to add it.

babel >= 0.9.6, < 2.4
waitress >= 0.8.8, < 1.0
pytest ~= 3.0
pytest-runner
pytest-sugar>=0.7.0
pytest-catchlog
pytest-localserver
mock
sphinx
webtest < 3