Add test cases for parsing filters in plot requests
Use the same sharding algorithm as bf-core in bf-elasticsearch

Partition data across elasticsearch indexes the same way we shard rollup
work. Use the same algorithm for consistency.
Do not override ES's default routing algorithm
Merge pull request #218 from lakshmi-kannan/bf_fix_stats

Add test cases for parsing filters in plot requests
Merge pull request #220 from dlobue/fix_es_sharding_and_partitioning

Fix es sharding and partitioning