We were seeing error on the last day of the month with TestProjectAllocatedBandwidthRetainTwo.
This is due to AddDate normalizes its result in the same way that Date does, so, for example,
adding one month to October 31 yields December 1, the normalized form for November 31."
I also fixed a minor UTC issue with this test as well.
Change-Id: I0157873e7befa57810e5f264a922b188890fa46a
Removes old project_bandwidth_rollups records that are no longer used.
Uses a retain months configuration to determine how many months to save. Current month cannot be removed.
Tests retainMonths=-1, 0, 2
Change-Id: Ia4be2546cdb28802427acf41ecd85ad66df3e62c