Fix validation when adding static columns

patch by slebresne; reviewed by iamaleksey for CASSANDRA-7730
Better error message when trying to add a collection with the same name than a previously dropped one
Merge branch 'cassandra-2.0' into cassandra-2.1.0

Conflicts:
	CHANGES.txt
	src/java/org/apache/cassandra/cql3/statements/AlterTableStatement.java
Merge branch 'cassandra-2.1.0' into cassandra-2.1
Give CRR a default input_cql Statement

Patch by Mike Adamson, reviewed by brandonwilliams for CASSANDRA-7226
Merge branch 'cassandra-2.0' into cassandra-2.1.0

Conflicts:
	CHANGES.txt
Merge branch 'cassandra-2.1.0' into cassandra-2.1
Merge branch 'cassandra-2.1' into trunk
Merge branch 'cassandra-2.1' into trunk

Conflicts:
	test/system/test_thrift_server.py
Prompt on missing dependency in cqlsh on Windows
Patch by Josh McKenzie, reviewed by Jonathan Ellis for CASSANDRA-7749
Remove Thrift Python tests (moved to dtests since CASSANDRA-5687)
Merge branch 'cassandra-2.1.0' into cassandra-2.1
Prompt on missing dependency in cqlsh on Windows
Patch by Josh McKenzie, reviewed by Jonathan Ellis for CASSANDRA-7749
Merge branch 'cassandra-2.1' into trunk
Pass mutated cf to index updater for use by PRSI

patch by Sam Tunnicliffe; reviewed by Aleksey Yeschenko for
CASSANDRA-7742
Merge branch 'cassandra-2.1.0' into cassandra-2.1
Merge branch 'cassandra-2.1' into trunk
Remove netty buffer ref-counting

Patch by tjake; reviewed by benedict for CASSANDRA-7735
Merge branch 'cassandra-2.1.0' into cassandra-2.1
Merge branch 'cassandra-2.1' into trunk