Expose CFMetaData#isDense()
Merge branch 'cassandra-2.0' into cassandra-2.1.0

Conflicts:
	src/java/org/apache/cassandra/config/CFMetaData.java
	src/java/org/apache/cassandra/cql3/statements/CreateTableStatement.java
Merge branch 'cassandra-2.1.0' into cassandra-2.1
Merge branch 'cassandra-2.1' into trunk