Metadata support for the NVP plugin

[Salvatore Orlando]

The Grizzly solution for Quantum metadata access currently won't work with plugin which do not use the L3 agent.

The Nicira plugin is one of those. We need to ensure this plugin is able to metadata proxies (both routed and non routed) and the metadata agent.

This is important, and therefore marked as 'high', as metadata server access is a fundamental feature provided by Quantum

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/21934

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/21934
Committed: http://github.com/openstack/quantum/commit/24c77966b6449257c2bfa87419aafc3bb5f3c287
Submitter: Jenkins
Branch: master

commit 24c77966b6449257c2bfa87419aafc3bb5f3c287
Author: Salvatore Orlando <email address hidden>
Date: Wed Feb 13 16:46:43 2013 -0800

    Metadata support for NVP plugin

    Bug #1121119

    Allows the NVP plugin to leverage the metadata proxy, by creating an
    ad-hoc topology for allowing access to a metadata proxy from a NVP
    router leveraging existing agents.

    This patch also removes previous code for metadata support in the
    NVP plugin, which was based on DHCP Option 121. This is now provided
    by the dhcp agent as well.

    Change-Id: If37ef388e063f40bb06908ee2f72c431f29dac31