update auth_token to support memcache

[Jesse Andrews]

With the landing of the redux branch we lost changes to auth_token.py that were made during essex (redux had the stable/diablo version).

We need to update this version to added memcache support for caching token validation

[Jesse Andrews (anotherjesse)]

Here was the E3 release: https://github.com/openstack/keystone/tree/milestone-proposed/keystone/

[Jesse Andrews (anotherjesse)]

https://bugs.launchpad.net/keystone/+bug/939015 might be caused by this bug

[Chmouel Boudjnah (chmouel)]

I have run a diff and here are the updated changes from legacy keystone :

- A service_ids feature which seems to be HP specific :
            self.service_id_querystring = '?HP-IDM-serviceId=%s' % \
                                (urllib.quote(service_ids))

- added Exceptions: ValidationFailed, TokenExpired

- service_timeout configuration variable to pass to http_connect
- auth_timeout configuration variable to pass to http_connect
- Cert/Key file.
- Token Caching.
- OS-KSValidate (???).
- More logging.
- Some function as staticmethods.

[Jesse Andrews (anotherjesse)]

Chmouel - can you open a bug for each of these (if applicable).

I've updated this bug to be about memcache feature of auth_token

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/4445

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/4445
Committed: http://github.com/openstack/keystone/commit/b5c8b3a81911491c97ee95e741c75ffd269f382a
Submitter: Jenkins
Branch: master

commit b5c8b3a81911491c97ee95e741c75ffd269f382a
Author: Chmouel Boudjnah <email address hidden>
Date: Fri Mar 2 15:31:54 2012 +0000

    Add token caching via memcache.

    - Fixes bug 938253
    - caching requires both python-memcache and iso8601

    Change-Id: I23d5849aad4c6a2333b903eaca6d4f00be8615d3