title: webpack-dev-server not working Cannot find module '../lib/polyfills'
body: <p>I moved my project to another computer, ran npm install. Project works fine except webpack-dev-server, it throws error</p>
  
  <pre><code>module.js:544
  throw err;
  ^
  
  Error: Cannot find module '../lib/polyfills'
      at Function.Module._resolveFilename (module.js:542:15)
      at Function.Module._load (module.js:472:25)
      at Module.require (module.js:585:17)
      at require (internal/module.js:11:18)
      at Object.&lt;anonymous&gt; (/project/node_modules/.bin/webpack-dev-server:6:1)
      at Module._compile (module.js:641:30)
      at Object.Module._extensions..js (module.js:652:10)
      at Module.load (module.js:560:32)
      at tryModuleLoad (module.js:503:12)
      at Function.Module._load (module.js:495:3)
  </code></pre>
  
  <p>What is it missing ?</p>