[maven-release-plugin] prepare release druid-0.6.71
[maven-release-plugin] prepare for next development iteration
Fix backwards compatibilty constant post aggregator
Merge pull request #431 from metamx/backwardscompatibilityfix

Fix backwards compatibilty constant post aggregator
prepare for next rel
[maven-release-plugin] prepare release druid-0.6.72
[maven-release-plugin] prepare for next development iteration
Fixed:

- Bad link for granularitySpec changed to real definition.
- All heads set to logical levels (consistent with all others).
- Fixed bad link in definition for spatialDimensions.
Merge branch 'master' into igalDruid
add router node
add tests
Merge pull request #432 from metamx/igalDruid

Igal druid
Merge
clean up failure scenarios
Merge pull request #434 from GuiSim/master

Small typo fixes in documentation
updated task ID definition
Add headers
merge changes from master
extend context to use map string object instead of map string string
fix serialisation of segmentMetaDataQuery