Updated config to stable/grizzly

Updated settings from the upstream stable/grizzly branch.
Kept the settings we originally had, and marked some that
may be removable.
  https://github.com/openstack/horizon/blob/stable/grizzly/openstack_dashboard/local/local_settings.py.example

Change-Id: I8bc4fa7c9c80cd93b84cfecdaebdb69f23565d4a
Merge "Updated config to stable/grizzly"