Added JSONScanPOP and JSONScanBatch
Repeated values in JsonRecordReader
Fix value vectors for e2e scan json pop
Fix late type binding for json record reader
Fix getBuffers and address comments
Fix VarLen getBuffers template and retain
Initial Parquet commit.  Suports INT, LONG, FLOAT, DOUBLE, distributed scheduling.
fixes for memory management and rpc throttling
Updates to add subscan support to JSON
cleanup comparison function tests. use a single json file, and abstract out redundant code.
Implement PartitionExchange Operator:
 - implement Partitioner template and code generation
 - implement OutgoingRecordBatch to manage records in the process of being sent to another host
 - implement PartitionSenderCreator and add visit method to ImplCreator
 - implement boiler plate for Hash DrillFunc
 - foreman: track intermediate nodes; not just leaf nodes.
 - code gen: implement generateMultipleOutputs() and getImplementationClassMultipleOutput(), similar to generate()
 - added FIXED_INT static output type determiner
 - fix parsing of "senders" in RandomReceiver
optimized generated code for partition sender
fix deadbuf issue when flushing an outgoing batch
prevent NPE in recordLoader.  still need to handle the last batch correctly.
fix issue with end of batch
Fix issue where redundant batches showing up after being partitioned and sent.
implement hash expression evaluation
fix schema path serialization
Fixes for Partitioner merge
Fix SQL parser logback file not found exception