PHOENIX-1401 SYSTEM.SEQUENCE table is not pre-split as expected

Conflicts:
	phoenix-core/src/main/java/org/apache/phoenix/util/UpgradeUtil.java
PHOENIX-1397 RVC combined with OR on first row key column results in NPE (Samarth Jain)

Conflicts:
	phoenix-core/src/main/java/org/apache/phoenix/compile/WhereOptimizer.java
PHOENIX-1401 SYSTEM.SEQUENCE table is not pre-split as expected