Rewrite "adding React to existing app"

[gaearon]

We should throw this way and start over.

https://reactjs.org/docs/add-react-to-an-existing-app.html

Instead it should be two steps:

• Add a React CDN script tag to your page
• Run Babel CLI on a directory to transform JSX/ES6 files into ES5

That's it. No package managers, no minifiers, no bundlers, etc.
We should move all that jazz somewhere else.

If you're adding React to an existing app, it's not our concern how you minify/bundle/etc. If you don't want to, it's really your business.

Otherwise we're looking clowny with all this setup.