Change the aggregate executor API and refactor related code
Merge branch 'master' of github.com:VoltDB/voltdb into ENG-6591-partial-aggregate
Fix the bad revert
Fix the wrong refactor again
Merge branch 'master' of github.com:VoltDB/voltdb into ENG-6591-partial-aggregate
compiler does not catch this memcheck problem
Merge pull request #1538 from VoltDB/ENG-6591-partial-aggregate

Eng 6591 partial aggregate