In RowDataResolver, reduce calls to replies.size(), and use replies.peek() instead of replies.iterator().next()
Merge branch 'cassandra-2.1.0' into cassandra-2.1
Merge branch 'cassandra-2.1' into trunk

Conflicts:
	src/java/org/apache/cassandra/service/AbstractRowResolver.java
	src/java/org/apache/cassandra/service/RowDataResolver.java