Fix broken paging state with prepared statement

patch by slebresne; reviewed by thobbs for CASSANDRA-7120
Remove bogus validation post-6855
Fix IllegalArgumentException in CqlStorage

patch by slebresne; reviewed by driftx for CASSANDRA-7287
Fix broken paging state with prepared statement

patch by slebresne; reviewed by thobbs for CASSANDRA-7120
Merge branch 'cassandra-2.1' into trunk

Conflicts:
	CHANGES.txt
Bump CQL version to 3.1.7, update CQL docs

Follow up for CASSANDRA-6875
Merge branch 'cassandra-2.0' into cassandra-2.1
Merge branch 'cassandra-2.1' into trunk
Support nul/non-existant fields in UDT

patch by slebresne; reviewed by iamaleskey for CASSANDRA-7206
Correctly name FileCache metrics.

Patch by Nick Bailey, reviewed by brandonwilliams for CASSANDRA-7294
Merge branch 'cassandra-2.0' into cassandra-2.1
Merge branch 'cassandra-2.1' into trunk
Bump cqlsh default CQL version to 3.1.7

Follow up for CASSANDRA-6875
Merge branch 'cassandra-2.1' into trunk
fix merge-created bad map key lookup type
Merge branch 'cassandra-2.1' into trunk
fix countAllBatches query
patch by Lyuben Todorov; reviewed by jbellis for CASSANDRA-7300
Merge branch 'cassandra-2.1' into trunk
cqlsh: always emphasize the partition key in DESC output

patch by Patrick McFadin; reviewed by Aleksey Yeschenko for
CASSANDRA-7274
Merge branch 'cassandra-2.0' into cassandra-2.1

Conflicts:
	CHANGES.txt
	bin/cqlsh