Updated German language file with missing strings and better Grammatic

Thanks for your fast additions!

I noticed the "Share" translation isnt being used. Not sure if that is "m24" as its "share" in english and i translated it of course in the german file. It still shows "Share". (It would need to be "Teilen" then under Help & Infos)

Grammatic of everything else is now double checked inside Chrome (not only in the text file) so everything fits together and sounds good.