title: How to override template_name in SelectDateWidget (Django 1.11)
body: <p>I need to wrap the fields in div. 
  In Django 1.10:</p>
  
  <pre><code>class CustomSelectDateWidget (SelectDateWidget):
      def render(self, name, value, attrs=None):
         ...
         output = []
         for field in self._parse_date_fmt():
              if field == 'year':
                  output.append('&lt;div class="input-field col s4"&gt;' + html['year'] + '&lt;/div&gt;')
              elif field == 'month':
                  output.append('&lt;div class="input-field col s5"&gt;' + html['month'] + '&lt;/div&gt;')
              elif field == 'day':
                  output.append('&lt;div class="input-field col s3"&gt;' + html['day'] + '&lt;/div&gt;')
          return mark_safe('\n'.join(output))
  </code></pre>
  
  <p>It dosn`t work in Django 1.11.
  I tried to override 'django/forms/widgets/select_date.html':</p>
  
  <pre><code>class CustomDateWidget(SelectDateWidget):
      def get_template_names(self):
          return ['accounts/custom_select_date.html']
  </code></pre>
  
  <p>But Django include 'django/forms/widgets/select_date.html' instead of my template 'accounts/templates/accounts/custom_select_date.html'. No error messages are displayed.</p>