title: Webpack returns status code 2
body: <p>I am using <a href="https://github.com/mxstbr/react-boilerplate" rel="nofollow">this</a> react boilerplate, but I don't think the issue is with the boilerplate itself. The boilerplate uses webpack v2.1.0-beta.15. I've haven't touched the webpack configuration files, but they do work. I must have broken something in my source, but have no idea where to even begin debugging.</p>
  
  <p>Upon building my source files using this command:</p>
  
  <pre><code>cross-env NODE_ENV=production webpack --config internals/webpack/webpack.prod.babel.js --color -p
  </code></pre>
  
  <p>The command <em>seems</em> to work properly - this is the output:</p>
  
  <pre><code>[1066] multi main 28 bytes {0} [built]
      + 1347 hidden modules
  </code></pre>
  
  <p>but the process returns status code 2.</p>
  
  <p>What does this mean? I've tried to find what's going wrong, but haven't been able to resolve the issue.</p>