[Sahara] Fix OSTF tests after a networking change

[Dmitry Mescheryakov]

After the following bug is fixed in Fuel 5.0
https://bugs.launchpad.net/fuel/+bug/1308541

the corresponding change must be made in OSTF tests to make them working

[Tatyanka (tatyana-leontovich)]

can not reproduce on 127 iso, so waiting for a change and re-verify

[Openstack Gerrit (openstack-gerrit)]

Fix proposed to branch: master
Review: https://review.openstack.org/89869

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/89869
Committed: https://git.openstack.org/cgit/stackforge/fuel-ostf/commit/?id=80930d65840356a8f5fc1c9c2b5e4333b675ac99
Submitter: Jenkins
Branch: master

commit 80930d65840356a8f5fc1c9c2b5e4333b675ac99
Author: Vadim Rovachev <email address hidden>
Date: Wed Apr 23 18:48:51 2014 +0400

    Rewrite base Class for sahara tests

    Sahara clean_up methods and tearDown corrected
    to properly remove data after run tests.
    Fixed create nodegroup_templates and cluster_templates
    for correctly work with/without autoassignment floating IP's.

    Change-Id: I66922eee3d99e2754e089d01222c6053ed795347
    Closes-Bug: #1311059
    Closes-Bug: #1311554