title: Can't resolve module 'child_process'
body: <p>I have an angular2 webpack project that is running in electron. I'm trying to use <code>shelljs</code> but webpack fails to build with the error:</p>
  
  <pre><code>[0] ERROR in ./~/shelljs/src/exec.js
  [0] Module not found: Error: Can't resolve 'child_process' in 'D:\Projects\angular-electron\node_modules\shelljs\src'
  [0]  @ ./~/shelljs/src/exec.js 6:12-36
  [0]  @ ./~/shelljs/src ^\.\/.*$
  [0]  @ ./~/shelljs/shell.js
  </code></pre>
  
  <p>My webpack configuration is targeting the <code>electron-renderer</code> and my polyfills are using <code>zone-node</code>:</p>
  
  <pre><code>return { 
      target: 'electron-renderer', //webpack-build-common.js
      ...
  </code></pre>
  
  <p>and</p>
  
  <pre><code>import 'zone.js/dist/zone-node'; //polyfills.ts
  </code></pre>
  
  <p>I have tried changing the webpack target to <code>node</code> but it has no effect.</p>
  
  <p>You can see my entire webpack configuration on <a href="https://pastebin.com/JREHZX9w" rel="nofollow noreferrer">paste bin</a></p>