StringInputRowParser: Treat dimensionExclusions case-insensitively
UniformGranularitySpec: Only return bucketInterval for timestamps that legitimately
overlap our input intervals
Rework DeterminePartitionsJob in the hadoop indexer

- Can handle non-rolled-up input (by grouping input rows using an additional MR stage)
- Can select its own partitioning dimension, if none is supplied
- Can detect and avoid oversized shards due to bad dimension value distribution
- Shares input parsing code with IndexGeneratorJob
DeterminePartitions follow-up

HadoopDruidIndexerConfig:
- Add partitionsSpec (backwards compatible with targetPartitionSize and partitionDimension)
- Add assumeGrouped flag to partitionsSpec

DeterminePartitionsJob:
- Skip group-by job if assumeGrouped is set
- Clean up code a bit
Merge branch 'master' into determine-partitions

Conflicts:
	indexer/src/main/java/com/metamx/druid/indexer/IndexGeneratorJob.java
Merge pull request #56 from metamx/determine-partitions

Determine partitions better