Broken link in README

[orta]

At the bottom there is

If you want to eject at some point, you may need to know a little bit more about Webpack. You can check out our [React & Webpack walkthrough here](./React & Webpack.md).

As there isn't a document for React + Webpack, perhaps it's worth linking to the create-react-app one?

[DanielRosenwasser]

Thanks @orta!