title: 'Options' object has no attribute 'getallrelated_objects' after Wagtail 1.11.1 Upgrade
body: <p>Just upgraded to 1.11.1, all fine locally but on our server we're getting </p>
  
  <p>wagtail AttributeError: 'Options' object has no attribute 'getallrelated_objects'</p>
  
  <p>on the new admin page navigation menu</p>
  
  <p>Any idea?</p>
  
  <p>Thanks</p>
  
  <p>Joss</p>