1) Fix bug with NPE thrown when requesting a dimension on a GroupBy query that is not dictionary encoded

1) Fix bug with SingleSegmentLoader.StorageLocation keeping track of its storage size incorrectly.  Add unit test ftw.

Improve runtime of segment distribution algorithm

Kafka protobuf

Robustness fixes for properly keeping track of when Segments are accessible

1) Add check in ServerManagerTest to make sure that the Segment has been "checked out" before the factory ever sees it.
2) Some code readability changes to ReferenceCountingSegment

update the server manager unit tests to check for the case where a segment may be accessed in toYield calls before an increment occurs

Make batch data segment announcer thread safe

1) Include new version of java-util to fix issue with resources not getting closed when an exception is thrown sometimes
2) Whitespace changes to GroupByQueryEngine

Retries for S3TaskLogs, S3DataSegmentPusher