Start date should after end date in calendar

[tinytmy]

Steps to reproduce:
1.when we launch to the Overview page the start date is the first day for every month(2014-04-01),
the end date is today(2014-04-18).
2.select the start date to 2014-04-12(do not after end date).
3.now we can select the end date before 2014-04-12

[Openstack Gerrit (openstack-gerrit)]

Fix proposed to branch: master
Review: https://review.openstack.org/89300

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/89300
Committed: https://git.openstack.org/cgit/openstack/horizon/commit/?id=fafbdc78e6168d98ef5a4bb038f742b318e453b2
Submitter: Jenkins
Branch: master

commit fafbdc78e6168d98ef5a4bb038f742b318e453b2
Author: tintmy <email address hidden>
Date: Mon Apr 21 12:04:56 2014 +0800

    Fix start date should after end date in calendar

    Start date should after end date in calendar

    Change-Id: I17a7679875716d9e39d29dc70d8bf0f9f2234d58
    Closes-bug:#1309339