[EPIC] Build Sphinx documentation into Gatsby site

[theresaanna]

• Research again and make sure no existing solution exists
• Write Gatsby module to take in Sphinx output

I think the module will accept Sphinx output in probably JSON?? I don’t think Sphinx does Markdown. Basically, Sphinx will be configured to write to a local directory, and the Gatsby module will ingest from that directory and the documentation content fed into components.

I don’t want to accept any input over HTTP because it introduces security implications and seems unnecessary for our purposes.