Catch annoying stats thread error when using HSQL backend
For ENG-4829, replace COWMap/Set with Cliff Click's NonBlockingHashMap/Set.
Fix fired asserts. Asserts get fired because EstTime is no longer
used for m_lastPendingWriteTime, so we can not predict accurate
interval number now.
For ENG-4763, use larger stack size in SingleThreadExecutor to avoid StackOverflowError when remote database is down
For ENG-4763, add apache tomcat connection pool to the third party readme
For ENG-4763, add tomcat to lib directory
Revert back to EstTime in NIOWriteStream.
modify parameter of getSingleThreadExecutor method
Replace ConcurrentSkipListMap with NonBlockingHashMap, and add third party license.
ENG-4870: Don't terminate ack tracking thread if the thread was interrupted.
Merge pull request #605 from VoltDB/ENG-4870-stream

ENG-4870: Don't terminate ack tracking thread if the thread was interrupted
Add PDFs of undated documentation to s/w kit.
Fix the wrong answer for extract function
Fix the fractional second library bug
Fix the fractional second part
Fix the test case
Fix the build on linux, static_cast problem
voltkvqa: split into a version without and with an export table, now two different catalogs are created
voltkvqa: update for join system test
Merge pull request #607 from VoltDB/quick-extract

Quick extract fix for 3.4.