Initializes the user stub using nosegae config magic

def _init_user_stub(self, **stub_kwargs):
        """Initializes the user stub using nosegae config magic"""
        # do a little dance to keep the same kwargs for multiple tests in the same class
        # because the user stub will barf if you pass these items into it
        # stub = user_service_stub.UserServiceStub(**stub_kw_args)
        # TypeError: __init__() got an unexpected keyword argument 'USER_IS_ADMIN'
        task_args = stub_kwargs.copy()
        self.testbed.setup_env(overwrite=True,
                               USER_ID=task_args.pop('USER_ID', 'testuser'),
                               USER_EMAIL=task_args.pop('USER_EMAIL', 'testuser@example.org'),
                               USER_IS_ADMIN=task_args.pop('USER_IS_ADMIN', '1'))
        self.testbed.init_user_stub(**task_args)