Fix potential SlabAllocator yield-starvation
patch by bes; reviewed by jbellis for CASSANDRA-7133
Merge branch 'cassandra-2.0' into cassandra-2.1
cqlsh: Accept and execute CQL statement(s) from command-line parameter

patch by Mikhail Stepura; reviewed by Brandon Williams for CASSANDRA-7172
Merge branch 'cassandra-2.0' into cassandra-2.1

Conflicts:
	CHANGES.txt
	bin/cqlsh
Merge branch 'cassandra-2.1' into trunk