Define Constants for IPv4 and IPv6 default addresses

[Vijay Chundury]

There are many references to 0.0.0.0/0 and ::/0 in Neutron code. It would be good to replace them with a constant and use the constant at various places.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/160782

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/160782
Committed: https://git.openstack.org/cgit/openstack/neutron/commit/?id=b80775010c1e518f8c94d82de0f8026a45cce342
Submitter: Jenkins
Branch: master

commit b80775010c1e518f8c94d82de0f8026a45cce342
Author: vijaychundury <email address hidden>
Date: Tue Mar 3 13:02:02 2015 +0000

    Replace IPv4 and IPv6 default addresses with constants

    At various places in Neutron we are using IPv4 and IPv6 default addresses in
    numeric format. This patch replaces them with constants to ensure consistency.

    Closes-Bug: #1427645
    Change-Id: I9817a95646546704e44fa70292eaa94635bb7395