Need more synchronizing in DruidDataSource.
fix stupidness with spatial indexing
Fix how metrics are emitted from servermanager
fix naming
add missing final
address cr
Merge pull request #659 from metamx/fix-metrics

Separate query metrics into scan/time and query/time
Coordinator drop/remove related stuff.

- DruidCoordinatorCleanup should wait for availableSegments to populate
  before dropping any segments.
- Clarify that millisToWaitBeforeDeleting applies to "removing" rather than
  "dropping" segments.
- LoadRule shouldn't need to wait for the deletionWaitTime before dropping
  excess replicas.
Merge pull request #661 from metamx/drop-remove-stuff

Coordinator drop/remove related stuff.
prepare for next release
[maven-release-plugin] prepare release druid-0.6.138
[maven-release-plugin] prepare for next development iteration
separate cleanup of overshadowed vs. unavailable segments
rename CleanupAvailable -> CleanupUnneeded
Merge pull request #662 from metamx/cleanup-cleanup

separate cleanup of overshadowed vs. unavailable segments
Merge branch 'master' into druid-0.7.x