support for 4 bytes for runId in metrics and a small bugfix in leveldb limit in getRow
Merge branch 'feature/metrics_increase_maxId_EntityTable' of github.com:caskdata/cdap into feature/metrics_increase_maxId_EntityTable

Conflicts:
	cdap-watchdog-tests/src/test/java/co/cask/cdap/metrics/data/AggregatesTableTestBase.java