title: Jquery-form-validator validate format date in datepicker
body: <p>I have form with input with date picker and I try to validate format date like <code>"yyyy-mm-dd"</code> when changed data in input. I install <code>jquery-form-validator</code> and write like this</p>
  
  <pre><code>&lt;form id="filter-form" action="my action" method="get"&gt;
    &lt;input type="text" name="to_date" id="to_datepicker" dataformatas="dd-mm-yyyy" data-validation-format="yyyy-mm-dd"&gt;
  &lt;/form&gt;
  </code></pre>
  
  <pre class="lang-js prettyprint-override"><code>$(document).ready(function() {
    var filterForm = $('#filter-form');
  
    filterForm.validate({
      rules: {
        from_datepicker: {
          required: true,
          date: true
        }
      }
    });
  
    $('#to_datepicker').datepicker({
      dateFormat: 'dd.mm.yy',
      showAnim: "drop",
      changeMonth: true,
      changeYear: true,
      showWeek: true
    });
  
  $('.hasDatepicker').on('change', function () {
      filterForm.submit()
  });
  </code></pre>
  
  <p>Then I try to write in input some data like <code>11111</code> but and <code>jquery-form-validator</code> is not called. How do I use this plugin? </p>