title: onchange event is not woking on flatpickr() input
body: <p>I have created a <strong>date picker</strong> with <code>flatpickr()</code> date picker is working fine. but I am trying to create an <code>onchange</code> event on that date picker but <code>onchange</code> event is not working I had tried to make a function like myfunction and call it on the input it is also not working </p>
  
  <p>so can anybody help me in this </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-js lang-js prettyprint-override"><code>$('.flatpickr').flatpickr();
     $("#flatpickr-disable-range").flatpickr({
      disable: [
       {
        from: "2016-08-16",
        to: "2016-08-19"
       },
       "2016-08-24",
       new Date().fp_incr(30) // 30 days from now
      ]
     });
  ( ".flatpickr" ).change(function() {
    alert( "Handler for .change() called." );
  });</code></pre>
  <pre class="snippet-code-html lang-html prettyprint-override"><code>&lt;script src="https://cdnjs.cloudflare.com/ajax/libs/flatpickr/4.5.7/flatpickr.min.js"&gt;&lt;/script&gt;
  &lt;script src="https://ajax.googleapis.com/ajax/libs/jquery/3.4.0/jquery.min.js"&gt;&lt;/script&gt;
  &lt;div class="form-group"&gt;
         &lt;input class="form-control flatpickr" id="set_exam_date" data-min-date="today" data-date-format="D F j, Y" placeholder="Select Date"&gt;
        &lt;/div&gt;</code></pre>
  </div>
  </div>
  </p>