fix bugs in balancing logic and removing auto-scaled node
[maven-release-plugin] prepare release druid-0.3.16
[maven-release-plugin] prepare for next development iteration
fixing a bug with indexing service not correctly killing worker nodes
fix broken UT
[maven-release-plugin] prepare release druid-0.3.18
[maven-release-plugin] prepare for next development iteration
1) Remove Task parameter from other methods off of TaskToolbox that required it
2) Move getTaskDir() off of TaskConfig and onto TaskToolbox
3) Rename SegmentKiller interface to DataSegmentKiller
4) Change signature of "DataSegmentKiller.kill(Collection<DataSegment>) throws ServiceException" to just kill(DataSegment) throws SegmentLoadingException
5) Add various log messages
6) Update the version of the segment that has been converted