PIG-3942: Util.buildPp() is incompatible with Non-MR execution engine (import
HExecutionEngine was omitted in previous commit)


git-svn-id: https://svn.apache.org/repos/asf/pig/trunk@1596035 13f79535-47bb-0310-9956-ffa450edef68
PIG-3945: Ant not sending hadoopversion to piggybank sub-ant (mrflip via cheolsoo)


git-svn-id: https://svn.apache.org/repos/asf/pig/trunk@1596059 13f79535-47bb-0310-9956-ffa450edef68
PIG-3936: DBStorage fails on storing nulls for non varchar columns (jeremykarn via cheolsoo)


git-svn-id: https://svn.apache.org/repos/asf/pig/trunk@1596061 13f79535-47bb-0310-9956-ffa450edef68
PIG-3944: PigNullableWritable toString method throws NPE on null value (mauzhang via cheolsoo)


git-svn-id: https://svn.apache.org/repos/asf/pig/trunk@1596062 13f79535-47bb-0310-9956-ffa450edef68
PIG-3940: NullPointerException writing .pig_header for field with null name in JsonMetadata.java (mrflip via cheolsoo)


git-svn-id: https://svn.apache.org/repos/asf/pig/trunk@1596063 13f79535-47bb-0310-9956-ffa450edef68
PIG-3941: Piggybank's Over UDF returns an output schema with named fields (mrflip via cheolsoo)


git-svn-id: https://svn.apache.org/repos/asf/pig/trunk@1596069 13f79535-47bb-0310-9956-ffa450edef68
PIG-3950: Removing empty file PColFilterExtractor.java speeds up rebuilds (mrflip via cheolsoo)


git-svn-id: https://svn.apache.org/repos/asf/pig/trunk@1596099 13f79535-47bb-0310-9956-ffa450edef68