Fix german translation in particular (manual as well as in infotainment)

The current translation of the manual for german is rather subpar - it takes a lot of thinking to deduce some of the meanings. Some paragraphs are completely illegible... Also in the infotainment there are some errors - most notably the shortcut for the heated mirrors is completely wrong as been translated to "rear window" - i could only deduce that by decrypting the symbolic icon next to it