ip_lib ensure_namespace has class name error

[Mark McClain]

ensure_namespace tries to instantiate a non-existent class when the namespace already exists.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/11171

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/11171
Committed: http://github.com/openstack/quantum/commit/f018dc51a7022fe7ccc09274a98fc6ecffb16d7d
Submitter: Jenkins
Branch: master

commit f018dc51a7022fe7ccc09274a98fc6ecffb16d7d
Author: Mark McClain <email address hidden>
Date: Fri Aug 10 14:24:17 2012 -0400

    fixes typo in ensure_namespace

    bug 1035425

    There was an uncheck branch in ensure_namespace that used the wrong
    class name. This fixes that bug and adds better tests.

    Change-Id: I0c22e70938305e180084de4bf9a700aebf512645