PIG-3395 Large filter expression makes Pig hang
Review Request #13186 - Created Aug. 1, 2013 and updated
Refactors PColFilterExtractor so that a large filter expression can be processed w/ reasonable heap size. Currently, a large filter expression that consists of more than 50 or/and expressions chokes Pig.
Adds new test cases to TestPartitionFilterPushDown. All unit tests pass.