Refactor Quota limit summary template

[Bradley Jones]

This review https://review.openstack.org/#/c/168335/ highlighted a need to change the limit summary template under certain conditions which is difficult with the current template.

The template needs to be re-factored to allow easier customisation and reflect the changes mentioned in review https://review.openstack.org/#/c/168335/

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/170147

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/170147
Committed: https://git.openstack.org/cgit/openstack/horizon/commit/?id=286245b423f0234d5d9ece50db83e23e2c24d8ba
Submitter: Jenkins
Branch: master

commit 286245b423f0234d5d9ece50db83e23e2c24d8ba
Author: Bradley Jones <email address hidden>
Date: Thu Apr 2 15:22:00 2015 +0100

    Refactor quota limit summary template

    Refactor the quota limit summary template to allow easier customisation.
    Also change it so that it removes the 'of' when there is no quota limits in
    place so that it just reads Used 'x' (No Limit).

    Added tests for checking usage['charts'] is in the context and that (No Limit)
    is present when there is an infinite quota on the page.

    Change-Id: Iba62ca89e53f0d6b9c583e4cc450e853c18ba107
    Closes-bug: 1439717