def warden.authenticate!
   1) find user by token
   2) token is perished
   3) authlogic session is created
  4) user is activated
end


def login_by_token
      warden.authenticate!(:scope => :cas, :action => 'unauthenticated')

      tgt = TicketGrantingTicket.new(username)
      tgt.save!(settings.redis)
      cookie = tgt.to_cookie(request.host)
      response.set_cookie(*cookie)
 end