Added German translation for intro.py

[janu75]

Hi Ben

I came across your Python Intro and thought I might give it a try for the upcoming GirlsDay at my company. As I am not sure how good the students English will be, I translated the comments to German language.

If you like, you can add this to your main repository, I think this is a good entry point for German students as well ;-)

Best regards, Jan