ENG-5021: enable reverse scan to optimize query with prefix filters and explicit DESC order.
ENG-5021: add junit tests.
Merge branch 'master' into ENG-5021
ENG-5021: remove unnecessary insert procedure in TestOrderBySuite.
ENG-5013: fix conversion of parameter from java double / float to decimal type.
ENG-5021: minor fix for one junit test.
ENG-5013: remove debug output.
ENG-5013: add more junit tests.
ENG-5013: add more junit tests.
Add null support for Decode function
Merge branch 'master' of github.com:VoltDB/voltdb into ENG-4949-decode-null
Update vis.py

performance graphs: increase default date range (all-time charts)
For ENG-4765, fix export to file command line timezone parsing
ENG-4760: split junit test into "junit_regression" and "junit_other"; and further split regression tests into "junit_regression_h1" and "junit_regression_h2".
ENG-5013: minor changes to TestSQLTypesSuite.
For ENG-5048, fix a bug in legacy export client where it would always reconnect on catalog update
Set longer TTL for Java DNS caching policy.

Successful DNS lookups will cache for 5 minutes.
Unsuccessful lookups will cache for 1 hour.
ENG-4760: refactor junit and junit_regression targets.
Add support for asynchronous/synchronous DNS lookups and rejigger hostname strings to always include the ip
Finally find a way to solve the null problem for Decode