title: Clear validation error message when the value is updated or selected
body: <p>I have form in yii that validates the form field. When I submit the form it shows the errors. 
  But when the value of the field with the validation error is updated, the error still present. 
  I want the message to clear. How should i clear the validation error?</p>
  
  <p>Below the form widget code </p>
  
  <pre><code>&lt;?php $form = $this-&gt;beginWidget('CActiveForm', array(
      'id'=&gt;'user-form',
      'enableAjaxValidation'=&gt;true
  )); ?&gt;
  </code></pre>
  
  <p>In my form I echo the validation error like the code below:</p>
  
  <pre><code> &lt;?php echo $form-&gt;error($model, 'firstname'); ?&gt; 
  </code></pre>
  
  <p>I tried the solution from this problem
  <a href="https://stackoverflow.com/questions/11469194/trigger-yii-field-validation-onchange-of-another-field">Trigger Yii field validation onchange of another field</a> </p>
  
  <pre><code>$('#user-form').change(function(){
  
      var settings = $(this).data('settings');
      $.each(settings.attributes, function () {
          this.status = 2; // force ajax validation
      });
      $(this).data('settings', settings);
  
      // trigger ajax validation
      $.fn.yiiactiveform.validate($(this), function (data) {
          $.each(settings.attributes, function () {
              $.fn.yiiactiveform.updateInput(this, data, $(this));
          });
  
      });
  });
  </code></pre>
  
  <p>But the error message is still not cleared. I have confirmed that the ajax request is sent and there are response as its showed on the firebug console.</p>
  
  <p>[EDIT]
  It seems those validation errors for "select" fields are the ones that are not updated/cleared only.</p>
  
  <p>[EDIT]
  All the validation errors that are printed/echo after the form is submmitted will not disappear even if the value is supplied or change to satisfy the validation rules.</p>