HTTP Negotiate workflow is now separated from the Django authentication
workflow so that you can inherit from the new NegotiateView and for
example implement a view which link a currently logged user to a
Kerberos identity or which allow to choose among a list of users linked
to a Kerberos identity.
An ajax mode was also added: if the view is called using XMLHttpRequest
and there is no 'next' param the view return JSON content 'true' if
authentication succeed, 'false' otherwise.
The keytab file must be passed using the usual KRB5_KTNAME environment
variable to the Django process, no need to use a custom setting for
that. For memory syntax is KRB5_KTNAME=FILE:/path/to/keytab