Support identity comparison of RelDataTypeDrillImpl.  Fix tpch query aliases in 04 and 09
Support CASE statement in query 1. Pending testcases
Modify StreamAggPrule to support no group by key case. Modify MergeJoin to reject cartesian join.
Use RexLiteral.type and RexLiteral.typeName while converting from Optiq to Drill literals.
Use IntExpressions for integer as opposed to DoubleExpression
serialize "and" function as "booleanAnd" to not confuse parser
Expression string builder bug, JODA cannot handle white space
implement function to cast from long to date, timestamp
fix or, query uncomment and add absolute reference.
Add the date expressions in the tpch queries
fix merging receiver
in partition sender, on Iteroutcome.STOP, cleanup without flushing
in partition sender, release incoming vectors after partitioning
set def recordCount for explain
Build the IfExpression correcty in ExpressionStringBuilder
Use IntExpression instead of LongExpression for integers
Create CastExpression and traverse visitor pattern while performing implicit cast in ExpressionTreeMaterializer.
Bug in DrillOptiq while generating cast functions to Float, Double, IntervalYear and IntervalDay
allocate 100 bytes/record for variable length in partition sender
DRILL-437: Add support for POSTFIX operators.
1. IS NULL/IS NOT NULL
2. IS TRUE/IS FALSE
3. IS NOT TRUE/IS NOT FALSE
Adjust project's trait field id based on the mapping from input to output.   Output Rel and Logicl Rel for debug purpose.
Revert "Create CastExpression and traverse visitor pattern while performing implicit cast in ExpressionTreeMaterializer."

This reverts commit b7c76c218a7359e99140bc8ee8eeef65f950d7ee.