Checkpoint work in progress
For ENG-4454, checkpoint progress in hashrange expression
For ENG-4454. add tests for hash range expression and fix discovered bugs
For ENG-4454, merge from master, fix issues with changes to JSON parsing
For ENG-4454, trailing bytes matter for the hash, need to always pad out to 8 bytes
For ENG-4454, fix bug pointed out by Ning handling ranges spanning Long.MIN to Long.MAX, and add a test for the condition
Merge pull request #452 from VoltDB/ENG-4454-2

ENG-4454: Add hash range expression for internal use.