Add German translation and update meetups page

[cmaureir]

Including the initial work from

https://github.com/PyLadiesBerlin/PyLadiesBerlin.github.io/pull/45

and adding new English-paragraphs based on the german text.

Closes #50

[cmaureir]

(cc @marenwestermann because I'd need a hand if I got it right in English of what @quosi wrote originally in German)