- The Configurator ``testing_securitypolicy`` method now returns the policy
  object it creates.

- The Configurator ``testing_securitypolicy`` method accepts two new
  arguments: ``remember_result`` and ``forget_result``.  If supplied, these
  values influence the result of the policy's ``remember`` and ``forget``
  methods, respectively.

- The DummySecurityPolicy created by ``testing_securitypolicy`` now sets a
  ``forgotten`` value on the policy (the value ``True``) when its ``forget``
  method is called.

- The DummySecurityPolicy created by ``testing_securitypolicy`` now sets a
  ``remembered`` value on the policy, which is the value of the ``principal``
  argument it's called with when its ``remember`` method is called.