title: Webpack with an array provided as config
body: <p>In this webpack starter kit <a href="https://github.com/webpack/react-starter">https://github.com/webpack/react-starter</a> I see the webpack.production.config.js module does not export only a config object but an array of config objects instead:</p>
  
  <pre><code>module.exports = [
      require("./make-webpack-config")({
          // commonsChunk: true,
          longTermCaching: true,
          separateStylesheet: true,
          minimize: true
          // devtool: "source-map"
      }),
      require("./make-webpack-config")({
          prerender: true
      })
  ];
  </code></pre>
  
  <p>What will happen in this case, when multiple config objects are provided? It isn't mentioned in webpack's docs</p>