Init documentation website

[ffelten]

Based on Farama template.

I initiated some pages but did not clean everything. I'm wondering how to avoid duplicating the README vs the website.

Testing

pip install . 
cd docs/
pip install -r docs/requirements.txt
make dirhtml _build

Open the docs/build/dirhtml/index.html using a browser

[ffelten]

I see this when I click on the side menu:

[mgoulao]

Building:

make dirhtml
python -m http.server  --directory _build

OR:

sphinx-autobuild -b dirhtml . _build