ENG-5901-real: make poison pill constant and refactor and merge from master.
ENG-5901-real: make poison pill constant and refactor and merge from master.

simonzhangsm/voltdb,deerwalk/voltdb,creative-quant/voltdb,simonzhangsm/voltdb,ingted/voltdb,deerwalk/voltdb,ingted/voltdb,ingted/voltdb,creative-quant/voltdb,paulmartel/voltdb,VoltDB/voltdb,zuowang/voltdb,zuowang/voltdb,deerwalk/voltdb,kumarrus/voltdb,ingted/voltdb,creative-quant/voltdb,simonzhangsm/voltdb,flybird119/voltdb,migue/voltdb,VoltDB/voltdb,kumarrus/voltdb,VoltDB/voltdb,kumarrus/voltdb,wolffcm/voltdb,ingted/voltdb,deerwalk/voltdb,creative-quant/voltdb,paulmartel/voltdb,flybird119/voltdb,paulmartel/voltdb,paulmartel/voltdb,creative-quant/voltdb,zuowang/voltdb,flybird119/voltdb,kumarrus/voltdb,wolffcm/voltdb,zuowang/voltdb,kumarrus/voltdb,VoltDB/voltdb,zuowang/voltdb,migue/voltdb,simonzhangsm/voltdb,zuowang/voltdb,paulmartel/voltdb,simonzhangsm/voltdb,wolffcm/voltdb,VoltDB/voltdb,wolffcm/voltdb,flybird119/voltdb,flybird119/voltdb,ingted/voltdb,zuowang/voltdb,deerwalk/voltdb,ingted/voltdb,wolffcm/voltdb,paulmartel/voltdb,zuowang/voltdb,paulmartel/voltdb,simonzhangsm/voltdb,ingted/voltdb,creative-quant/voltdb,migue/voltdb,kumarrus/voltdb,migue/voltdb,wolffcm/voltdb,migue/voltdb,migue/voltdb,migue/voltdb,flybird119/voltdb,migue/voltdb,deerwalk/voltdb,deerwalk/voltdb,simonzhangsm/voltdb,creative-quant/voltdb,creative-quant/voltdb,deerwalk/voltdb,paulmartel/voltdb,kumarrus/voltdb,flybird119/voltdb,wolffcm/voltdb,flybird119/voltdb,wolffcm/voltdb,VoltDB/voltdb,kumarrus/voltdb,simonzhangsm/voltdb,VoltDB/voltdb