title: Calculate Date Duration
body: <p>I have to calculate the duration of two dates with days and hours remaining.</p>
  
  <p>If the two dates have different days, I need to return the duration in days and hours.</p>
  
  <p>For example, given the following input:</p>
  
  <blockquote>
    <p><code>2016-12-11T09:30:00.000Z</code>  and <code>2016-12-12T11:30:00.000Z</code></p>
  </blockquote>
  
  <p>I would like to have this output:</p>
  
  <blockquote>
    <p>1 day 2 hrs </p>
  </blockquote>
  
  <p>How to achieve this using moment.js?</p>