DRILL-1103: Cleanup java-exec POM to make it more eclipse friendly

* Replaced maven-antrun-plugin with maven-resource-plugin
* Altered the execution life-cycle of some of the plugin execution.
DRILL-1104: Increase MaxDirectMemorySize to 3G for unit tests
DRILL-794: Fix IOB while performing decimal subtraction
DRILL-923: Bit-wise and logical Aggregate functions
DRILL-967: Age and shift functions.
DRILL-1074: Fix computation of scale for divide function.
DRILL-1105: Fix bug in streaming aggregate when first batch is empty
DRILL-1099: Inject space (' ') as the default second argument to [lbr]trim

* Optiq already handles this for "trim".
DRILL-1085: Round up while casting to int/bigint from float/double/decimal
DRILL-1106: Fix race condition in incoming buffers
DRILL-1107: Handle case in Hash join where first batch has zero records

Handle case in merging receiver when first batch has zero records
DRILL-1102: Use same set of keys to distribute left and right side of join operator. Add option of hashing on single join key.