added german language files

[temmiland]

Context

• This PR adds german language support for the docusaurus.

Choices

Test instructions

1. Navigate to the docusaurus folder
2. Run: npm start -- --locale de

Checklist before requesting a review

• I have performed a self-review of my code
• I've added documentation about this change to the README.
• I've not introduced breaking changes.

[temmiland]

Hi 😄
I just wanted to make it clear that I've started translating, not that several people are making the effort at the same time and can translate together instead.

Please only merge when everything is translated.

[MSpreckels]

you might want to mark it as draft if you dont want @thijsvanloef to merge it :)

[temmiland]

Hey guys 👋🏼
I squashed my commits into one commit, so that everything is easier to maintain 😄

I also checked that everything looks good in docusaurus and checked the links pointing to headings hopefully work in production. I used the Dutch language files as a guide because it works there.

In the meantime there have been markdown lint checks. Unfortunately I can't see the current status.

If there is anything that needs to be fixed, please let me know. 😊

[MSpreckels]

Hey there! I've skimmed over the translation and found a few things. IMO, it's an accurate translation which sometimes feels abit stiff.

[temmiland]

Hi thanks! I have added your suggestions. I also tried not to change too much of the meaning and form of the original texts. And in some places it was actually a bit stiff.