DRILL-918: During Sort, handle the case where the child SelectionVector produces 0 records.
DRILL-799: Use static constants instead of Math.pow() to compute powers of 10 while adjusting scale of decimal data type.
DRILL-913: Fix IOOB in HashJoinProbe when input is empty batch
DRILL-924: Update trim so that it synchronized within the arena to avoid inconsistent state.
Fix DRILL-926: Index out of bound exception when creating outgoing filter record batch when incoming SV mode is NONE.
Logging to track allocator initial reservation
Reset fragment allocation for each minor fragment
more logging in streaming agg
enable extra debug on stream agg
add additional logging messages.
Reset outputCount on each outgoing batch in Streaming Aggregate
Disable EXTRA_DEBUG in streaming agg
Fix an issue with keys output for multiple output batches of hash aggregate.
Make sure all minorFragments get work in scan
Update Data Collection and batch buffers to one or all streams for auto read depending on use.
reduce logging statement overhead in removing record batch
DRILL-887: TestQueriesOnLargeFile.testMergingReceiver fails on Windows
Enable View persistence, Storage Plugin and System option persistence.

Conflicts:
	exec/java-exec/src/main/java/org/apache/drill/exec/ExecConstants.java
	exec/java-exec/src/test/java/org/apache/drill/exec/cache/TestCacheSerialization.java
Adding HBase Persistent Store.

+ Modified some interfaces and configuration keys.

Conflicts:
	exec/java-exec/src/main/java/org/apache/drill/exec/ExecConstants.java
Delete views after test and close ResultSet objects after use