title: Nodemon crashes and shows waiting for file changes
body: <p>I am using nodemon version 1.18.3 and express version 4. 
  Upon running nodemon command directly, I get the following error:</p>
  
  <p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
  <div class="snippet-code">
  <pre class="snippet-code-html lang-html prettyprint-override"><code>events.js:165
        throw er; // Unhandled 'error' event
        ^
  
  Error: listen EADDRINUSE :::3000
      at Server.setupListenHandle [as _listen2] (net.js:1346:14)
      at listenInCluster (net.js:1387:12)
      at Server.listen (net.js:1475:7)
      at Function.app.listen (/home/rishabh/Documents/my_projects/getting_MEAN/loc8r/node_modules/express/lib/application.js:531:24)
      at Object.&lt;anonymous&gt; (/home/rishabh/Documents/my_projects/getting_MEAN/loc8r/bin/www:7:18)
      at Module._compile (internal/modules/cjs/loader.js:654:30)
      at Object.Module._extensions..js (internal/modules/cjs/loader.js:665:10)
      at Module.load (internal/modules/cjs/loader.js:566:32)
      at tryModuleLoad (internal/modules/cjs/loader.js:506:12)
      at Function.Module._load (internal/modules/cjs/loader.js:498:3)
  Emitted 'error' event at:
      at emitErrorNT (net.js:1366:8)
      at process._tickCallback (internal/process/next_tick.js:178:19)
      at Function.Module.runMain (internal/modules/cjs/loader.js:697:11)
      at startup (internal/bootstrap/node.js:201:19)
      at bootstrapNodeJSCore (internal/bootstrap/node.js:516:3)
  [nodemon] app crashed - waiting for file changes before starting...</code></pre>
  </div>
  </div>
  </p>
  
  <p>Nodemon crashes and keeps on waiting for file changes. </p>