translate client routes

[jankapunkt]

Routes are fixed in english, however, we should have routes defined for the user's current language and they should also be interchangeable, for example:

• en: /lesson/:lessonId
• de: /unterricht/:lessonId

As shown above, the translation should not affect the route parameters (here: :lessonId) as they are converted to the corresponding parameter value (here: the _id of the lesson to enter).

If a user enters a route of foreign language then they should still land on the correct page. One approach to implement this would be to

• first check if the route resolves in the user's current language
• if this fails, check if the route resolves for any other language, that defines routes
• if this fails redirect to not-found route