title: Add existing dependencies to bower.json
body: <p>I accidentally did </p>
  
  <pre><code>bower install jquery
  </code></pre>
  
  <p>without the <code>--save</code> flag. So this package isn't saved in the dependencies section in bower.json</p>
  
  <p><strong>Is there a command I can run to add all installed packages into the dependency list?</strong></p>