Add support for PERCENT_NULL for statistic table
get rid of compiler warnings for EE check
Merge branch 'master' of github.com:VoltDB/voltdb into ENG-5881-tuple-percentage
Merge pull request #1218 from VoltDB/ENG-5881-tuple-percentage

Eng 5881 tuple percentage
Do not realize that PRO still use the validStatisticsForTableLimit function
Merge branch 'ENG-5881-tuple-percentage' of github.com:VoltDB/voltdb into ENG-5881-tuple-percentage
Merge branch 'master' of github.com:VoltDB/voltdb into ENG-5881-tuple-percentage
Merge pull request #1221 from VoltDB/ENG-5881-tuple-percentage

Eng 5881 tuple percentage r=pmartel