Improve unit test coverage for Cisco plugin nexus code

[Henry Gessau]

Improve unit test coverage for ...

quantum/plugins/cisco/nexus/cisco_nexus_network_driver_v2 100 24 0 26 1 72%
quantum/plugins/cisco/nexus/cisco_nexus_plugin_v2 117 23 0 12 2 79%

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/57100

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/58380

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/57100
Committed: http://github.com/openstack/neutron/commit/26e9fad61f86bedd16179ede9736b56c4a9a5752
Submitter: Jenkins
Branch: master

commit 26e9fad61f86bedd16179ede9736b56c4a9a5752
Author: Dane LeBlanc <email address hidden>
Date: Thu Nov 21 13:13:02 2013 -0500

    Improve unit test coverage for Cisco plugin nexus code

    Closes-Bug: #1190622

    This fix improves the unit test coverage for the Cisco Nexus plugin's
    cisco_nexus_network_driver_v2.py and cisco_nexus_plugin_v2.py
    source files from:
    cisco_nexus_network_driver_v2: 72%
    cisco_nexus_plugin_v2: 79%
    To:
    cisco_nexus_network_driver_v2: 99%
    cisco_nexus_plugin_v2: 94%

    Much of what the remaining "uncovered" code (coverage tool
    reports as partially covered) can be attributed to the
    coverage tool not being aware that execution does not
    continue at the end of a save_and_reraise_exception()
    context block (i.e. the exception will be reraised, but
    the coverage tool isn't aware of this).

    This fix and coverage results are dependent on the fix for #1246080.

    Change-Id: Ie0e11fc0a12502739fb39bb4b30deb04dd31b7b0