Docusaurus setup + refactor

Docusaurus supports everything 11ty does but allows us to add custom pages easier while sharing the same style configuration.

At time of writing, this PR contains just the prototype/POC which is deployed here

This migration will take a while, anyone should feel free to contribute to any part of the requirements below.

Requirements necessary before ready for review:

Conformation and benchmarks migrated to React and inside this PR
Modify docusaurus config to use same colors as previous site
Come up with a nice landing page
Either make use of Tutorial pages specific to Boa or remove it.
CI/CD
- Publish boa_wasm to npm
- Conformation and benchmarks should push json results to this repo
- Auto deploy to github pages

boa-dev / boa-dev.github.io