OVSInterfaceDriver should use ovs_lib not call ovs-vsctl directly

[Cedric Brandily]

ovs_lib module is responsible for the interaction with OVS but OVSInterfaceDriver._ovs_add_port() method calls directly
ovs-vsctl which implies inconsistencies: ovs_lib calls ovs-vsctl with a timeout but not OVSInterfaceDriver._ovs_add_port().

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/137303

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/137303
Committed: https://git.openstack.org/cgit/openstack/neutron/commit/?id=7c3921585e404c31272c4d31ed326f7323c062d8
Submitter: Jenkins
Branch: master

commit 7c3921585e404c31272c4d31ed326f7323c062d8
Author: Cedric Brandily <email address hidden>
Date: Wed Nov 26 00:31:22 2014 +0000

    Remove ovs-vsctl call from OVSInterfaceDriver

    ovs_lib module is responsible for the interaction with OVS but
    OVSInterfaceDriver._ovs_add_port() method calls directly
    ovs-vsctl which implies inconsistencies: ovs_lib calls ovs-vsctl
    with a timeout but not OVSInterfaceDriver._ovs_add_port().

    This change moves ovs-vsctl call in OVSInterfaceDriver._ovs_add_port
    to ovs_lib.

    Closes-Bug: #1396489
    Change-Id: I4d03f8beef2c5f2366ad2d1cf5f0b18b4f2857cd