The pyramid.security Authorization API function has_permission is made availble on the request.
The pyramid.security Authentication API functions are now available as
properties (unauthenticated_userid, authenticated_userid, effective_principals)
and methods (remember_userid, forget_userid) on pyramid.request.Request.

Backwards compatibility:
    For each of the APIs moved to request method or property, the orginal API in the pyramid.security module proxies to the request.

Reworked tests to check module level b/c wrappers call through to mixins for each API.
Tests that check no reg on request now do the right thing.

Add securiy authn and authz mixins to the dummy request used in test module in order
to get the tests passing.