RFR: Add polished tools to resurrect from any data loss

At Rackspace, we operate at scale processing (ingest+rollup) 2.2 MM metrics/min. Sometimes we have outages, wherein we need to resurrect data under different conditions. Two of the most common conditions are 1) We did not calculate rollups for certain subsets of metrics, but we ingested raw metrics and they haven't ttl'd out 2) We either did not ingest raw metrics or we ingested raw metrics but did not calculate rollups before they ttl'd out

This PR adds two tools under the module `blueflood-rollupTools` for dealing with both these situations:

1. `blueflood-rollupTools/ManualRollupTool` calculates out-of-band rollups for the given shards and between the supplied start and stop times from raw data
2. `blueflood-rollupTools/CloudFilesBackfiller` fetches raw data(Remember it has either not been ingested or has ttl'd out!) from out cold storage in Cloud Files and calculates 5m rollups(finest rollup granularity) on the fly. In order to calculate the rollups for coarser granularities, we calculate 5m rollups first and then run the `ManualRollupTool` to calculate for higher ones.