In 7d, before Babel, Webpack chokes at index.js, not App.js

[frozenzia]

In the section headed Loaderit, and just before that starts, we try to bundle the app after changing index.js to include JSX <App />, and this is where the bundler fails (at least for me?), as opposed to the way the documentation has it -- not failing until it hits the JSX in App.js. TOTALLY minor issue, and the problem is still the same -- we need to include the Babel loader.