Neutron rest test case should not override setupClass() method

[Lin Hua Cheng]

The setupClass() is overridden, this will cause issue in the future, plus it is overridden without calling super().

https://review.openstack.org/#/c/158867

the broken tests is exposed when it runs in django18

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/208781

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/208781
Committed: https://git.openstack.org/cgit/openstack/horizon/commit/?id=a354f016abec257891a53277dc936db3fdf65e6c
Submitter: Jenkins
Branch: master

commit a354f016abec257891a53277dc936db3fdf65e6c
Author: lin-hua-cheng <email address hidden>
Date: Mon Aug 3 20:33:59 2015 -0700

    Use setUp() method for neutron rest test

    There is no reason to override the setUpClass() in the test
    case. For data setup, the setUp() should be used.

    There is also an issue where the code is not calling super()
    class, this issue is exposed when running the test in django18.

    Closes-Bug: #1481143
    Partially Implements: blueprint django18

    Change-Id: Ic64cc0a5f0c7d0476bfac63b6e23fe8a1461d6ef