title: How to configure haystack for elasticsearch 5.0 in django settings?
body: <p>I just upgraded elasticsearch to 5.0.0 .
  I have django 1.7.7 and django-haystack 2.4.1 .</p>
  
  <p>In elasticsearch 5.0.0, Authorization header has been added for security purpose.</p>
  
  <p>So while making connection to elasticsearch through django, it's throwing error <strong>elasticsearch.exceptions.AuthenticationException: TransportError(401, u'security_exception')</strong></p>
  
  <p>Where can we add the Authorization field in haystack configuration?</p>