[Feature Request]: Docusaurus integration

[geromegrignon]

Relevant Scope

Other: describe below

Description

### Current status

The content of each markdown file is quite long.
Each file is full of links, making it difficult to navigate through the specs.
With the V2, specs will be longer to align with modern standards

Describe the solution you'd like

I'm considering adding Docusaurus to this repository and hosting it with Github Pages.

Benefits:
- a better user experience
- a versioning solution which help the transition to the V2


Here are the Docusaurus docs showcasing the solution: https://docusaurus.io/docs

Describe alternatives you've considered

At this point, Docusaurus is an arbitrary choice as it's one of the few solutions I'm aware of. I'm open to related alternatives.

[geromegrignon]

The documentation is now live on GitHub Pages: https://gothinkster.github.io/realworld/
I moved the existing documentation, additional tasks will be required to improve it.

I updated the description of the repository :