Replace GitBooks [deprecated] with alternative like docusaurus

[sakirma]

Hello, as the title suggests. I'd think it would be nice for future developers to use a documentation tool which is not deprecated.

I made a quick research which library would be best candidate and stumbled on Docusaurus.

• It has support for plugins
  • in this case a plugin for Open-Api. This would support the swagger file
• It is maintained by a large community
• Also has integrated internalisation feature.

If you don't like this issue to be placed here, then I could try to do this myself and if you like it then you could fork it officially into your project :)