Handle KeyboardInterrupt properly in cqlsh

Patch by Jordon Pittier, reviewed by brandonwilliams for CASSANDRA-5481
Merge branch 'cassandra-1.2' into cassandra-2.0
Handle paged results in cqlsh

Patch by Tyler Hobbs; review by Aleksey Yeschenko for CASSANDRA-7625
Backport CASSANDRA-6747

patch by yukim; reviewed by krummas for CASSANDRA-7560
Merge branch 'cassandra-2.0' into cassandra-2.1.0