Reference page documentation workflow proposal

[joeyklee]

Just a thought about a workflow that might be good to implement regarding adding documentation the ml5-library and the website. I'd rather create less overhead so maybe this proposal doesn't make sense. Ideally we could have [jsDoc](https://devhints.io/jsdoc_ running at some point, but maybe this is a start?

for example: if we update sketchRnn:
Make changes to ml5-library/src/sketchRnn/index.js ==> update ml5-library/docs/api-sketchRnn.md ==> copy the contents of that file to ==> ml5-website-2/reference/api-sketchRnn.md