Replace README with a link to Docusaurus page

[thijsvanloef]

Context

Since we are using docusaurus, I want to use a single place to store all of the documentation.
This way we do not need to keep updating the README.md in github and only the docusaurus documentation.

Choices

I decided to do this since the docusaurus is easier to navigate and has a search function, in my opinion this makes it easier for people to find what they need.

Test instructions

Click on the link, navigate to https://palworld-server-docker.loef.dev/

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.