Updated german translation for 3.0.0

Hey,
Here's my translation for the newest translation, I only added the translated changes from 3.0.0
I hope the format is correct and I'd also be willing to contribute to future translations.

If that's OK for you ;)
I'm 1/2 Swiss and 1/2 German and I have many years of English experience... so I think I've got enough translation skills. (At least I hope so)

Have a great week,
LibertyMarine
Merge pull request #682 from LibertyMarine/patch-1

Updated german translation for 3.0.0