Adding missing indexes on usage data
Using audit_period_ending in _verify_for_delete

The previous logic used the raw's timestamp, which could end up
    slightly outside of the audit period. This would give us a
    small window where a delete could happen outside of the
    audit period, but we'd still detect it. The new logic uses
    the exact end of the audit period.
Starting usage auditor
Merge branch 'master' of git://github.com/rackerlabs/stacktach into auditor_cron
Continuing usage auditor
Merge pull request #69 from ramielrowe/auditor_cron

Nova Usage Auditor Cron Job