title: Creating a date range fields with pikaday datepicker
body: <p>I'm trying to use the pikaday datepicker, I'm trying to avoid jquery datepicker because of its dependancies and heavy images, but I can't achieve what I want with pikaday.</p>
  
  <p>I have a from to field in a form, The date that can be selected in the to field shouldn't be past to the from field.. I tried like below but it is not working.</p>
  
  <pre><code>var picker = new Pikaday({
      field: document.getElementById('start')
  });
  var picker2 = new Pikaday({
      field: document.getElementById('end'),
      minDate: new Date(document.getElementById('start').value)
  });
  </code></pre>
  
  <p>A Pure javascript solution is better for me, 
  Anyone can guide me in this problem?</p>