PHOENIX-1402 Don't recalculate stats on split

Conflicts:
	phoenix-core/src/main/java/org/apache/phoenix/coprocessor/UngroupedAggregateRegionObserver.java
	phoenix-core/src/main/java/org/apache/phoenix/iterate/ParallelIterators.java
	phoenix-core/src/main/java/org/apache/phoenix/schema/stats/StatisticsCollector.java
	phoenix-core/src/main/java/org/apache/phoenix/schema/stats/StatisticsUtil.java
	phoenix-core/src/main/java/org/apache/phoenix/schema/stats/StatisticsWriter.java
PHOENIX-1416 Given a schema name, DatabaseMetadata.getTables and getColumns calls erroneously match tables without schema
PHOENIX-1413 Add Phoenix coprocessors with configurable priority

Conflicts:
	phoenix-core/src/it/java/org/apache/phoenix/hbase/index/covered/EndToEndCoveredColumnsIndexBuilderIT.java
	phoenix-core/src/main/java/org/apache/phoenix/hbase/index/Indexer.java
	phoenix-core/src/main/java/org/apache/phoenix/query/ConnectionQueryServicesImpl.java
	phoenix-core/src/main/java/org/apache/phoenix/query/QueryServicesOptions.java
PHOENIX-1394 getColumnDisplaySize() method returns incorrect value for varchar columns (Samarth Jain)
PHOENIX-1418 Optionally display number of parallel chunks in explain plan

Conflicts:
	phoenix-core/src/it/java/org/apache/phoenix/end2end/StatsCollectorIT.java