add test case for alias of string functions
make SUBSTR support 3rd parameter as optional
make substring support 3rd parameter as optional
add simple test for substr,substring with 2 parameters
fix comment format for previous work
Merge branch 'master' into ENG-3283-ALIASES-for-string-func
Drop failed attempt to set timezone in HSQLInterface
Test options for varbinary insert
ENG-6874 implement ByteBufferOutputStream
ENG-6874 fixed license check failures
ENG-6874 http export client emits avro encoded content
Merge branch 'master' into ENG-3283-ALIASES-for-string-func
Update PDFs for 4.7

(cherry picked from commit 44fbb15eea1beab68f549fd10c3b9c29c4e61b62)
Check point for re-entrant index access, still has failuere on the index access, investigating
ENG-6874 simple ByteBuffer(Input|Output)Stream unit test
Use char array to store the iterator pointer instead
upgrade guava to v18
ENG-6874 fix license check failure for TestByteBufferStreams
revert the change to the tests and turn off the output message later
Merge branch 'master' of github.com:VoltDB/voltdb into ENG-6880-concurrent-access