title: CSS Modules class names undefined
body: <p>I try to use css modules in my project. I'm using latest Create React App with react-scripts version 2.1.8. 
  In the <a href="https://facebook.github.io/create-react-app/docs/adding-a-css-modules-stylesheet" rel="nofollow noreferrer">docs</a> it says I can add CSS Modules, and i dont have to do eject script.</p>
  
  <p>I tried to do the same way, but my styles are empty and classes are undefined.
  Here is the code for one of my components:</p>
  
  <pre><code>import React, { Component } from 'react';
  import styles from './Catalog.css';
  
  class Catalog extends Component{
  
  render() {
      console.log('styles.catalog '+ styles.catalog); //returns: styles.catalog undefined.
      return (
        &lt;div className={styles.catalog}&gt; //returns: &lt;div&gt;
          ...
        &lt;/div&gt;
      )
  }
  </code></pre>
  
  <p>Catalog.css:</p>
  
  <pre><code>.catalog {
    min-width: 800px;
  }
  </code></pre>