Using a localization platform to translate [RFC]

Suggestion: handle translations using a localization platform as Crowdin https://crowdin.com or Transifex https://www.transifex.com
This would help translators with clean work and get help from people that are translators and not coders or "Git enabled" people!
Why using online platforms?

• People just need just their browsers to translate
• Its easy to know what is to be translated and to manage collaborative translations
• Have translations tools, translation memory, glossaries and so on.
• Are free for opensource projects.
• You can setup auto-update master files from github.
• API are available to automate things.
• Then you can use a tool to mass download or the API to download translations and upload them to Github.
• Non translated strings are empty on the platforms but auto-filled with english strings when downloaded.

Take a look into Calibre https://www.transifex.com/calibre/calibre or Koreader https://www.transifex.com/houqp/koreader/

Note: I can help you set up the projects and upload translations (but not the API part!). What is needed is a cleaned translations set (just the translated strings without the "to be translated" strings)

The issue names no files, tests, or entry points. Start by reviewing the Crowdin and Transifex examples linked in the description, then determine the required cleaned translation set and which platform and automation responsibilities are in scope. Done means the project has agreed on a localization platform and an actionable translation workflow.