fix cassandra stress errors on reads with native protocol

patch by belliottsmith; reviewed by jasobrown for CASSANDRA-7033
Post-CASSANDRA-7058 fix
Merge branch 'cassandra-2.0' into cassandra-2.1

Conflicts:
	src/java/org/apache/cassandra/service/StorageProxy.java
Merge branch 'cassandra-2.1' into trunk

Conflicts:
	tools/stress/src/org/apache/cassandra/stress/operations/CqlIndexedRangeSlicer.java
	tools/stress/src/org/apache/cassandra/stress/operations/CqlReader.java