Update Cisco VPN device driver

[Paul Michali]

Based on recent updates to the Cisco CSR REST APIs, update the Cisco device driver for VPN to sync up with those changes.

This includes

- Support for various IKE and IPSec encryption modes.
- Support for disable of anti-replay-window-size
- Cleanup UTs based on verified changes
- Enhance UT coverage for new REST API capabilities

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/86129

[Openstack Gerrit (openstack-gerrit)]

Reviewed: https://review.openstack.org/86129
Committed: https://git.openstack.org/cgit/openstack/neutron/commit/?id=cb948a47058d96b35ddf555d02962088461af6b6
Submitter: Jenkins
Branch: master

commit cb948a47058d96b35ddf555d02962088461af6b6
Author: Paul Michali <email address hidden>
Date: Fri Apr 4 19:14:36 2014 +0000

    Support enhancements to Cisco CSR VPN REST APIs

    Incorporate latest enhancements and fixes in Cisco CSR router REST API
    to the VPNaaS device driver and unit test cases. Primarily, is support in
    the REST API for different IKE and IPSec encryption algorithms, name length
    error handling, disable of anti replay window, and IKE keep alive.

    Also includes minor typos and comment fixes mentioned in previous reviews.

    Note: notest_cisco_csr_rest.py, which tests the CSR REST client, is not
    part of the UT suite yet, pending resolution of httmock package inclusion
    as test requirement.

    Change-Id: I931f487fbd4ead93a1648e89c9c383b3d55fc07c
    Closes-Bug: 1303820