ENG-4133: Prettier and less redundant logging on update catalog
ENG-4133: Tweak the logging of UACs.
Fix a bug Izzy found in review.
Add an extra tuplecount check during schema change (not technically part of ENG-4133).
Merge remote-tracking branch 'origin/master' into ENG-4133-uac-log
ENG-4133: Fix stupid C++ warning.
For ENG-4519, add cancellable watch to avoid double handling truncation requests
Merge pull request #455 from VoltDB/ENG-4133-uac-log

ENG-4133: Prettier and less redundant logging on update catalog
ENG-4571: If the snapshot doesn't have a digest file, it ain't a
snapshot.  Reject-a-rino.

r=nshi
Merge pull request #463 from VoltDB/ENG-4519

For ENG-4519, add cancellable watch to avoid double handling truncation requests
ENG-4576: When scanning snapshots for recovery, include the catalog
file.  When evaluating snapshots for complete-ness, check for the
presence of the catalog file and a valid CRC.
ENG-4576: Add the catalog jar file pass to SpecificSnapshotFilter for
consistency's sake, even though the current callers don't need the
catalog.
Merge pull request #464 from VoltDB/eng4576

ENG-4576: Include catalog sanity checks in snapshot completeness criteria
ENG-4572: Port runtime-modifiable heartbeat timeout change to master,
part 1.  This half would allow the setting to be updated if it made it
through the catalog diff whitelist.  That change is in the pro repo.
ENG-4572: Port "Log every 10 seconds you don't hear from a foreign host"
to master.
ENG-4572: Fix licenses for licensecheck
Merge pull request #465 from VoltDB/eng4572

ENG-4572: porting heartbeat timeout configuration to master
Correction to tools/demo instructions

Need to cd to voter or voltkv directory before running ./run.sh because
srccompile uses relative paths.
Merge branch 'master' into ENG-4579
Updats based on nshi review