Tests for CASSANDRA-6839
Add test coverage for IN operator on column conditions
Accept null values in element access column conditions

Done for CASSANDRA-6839
Merge branch 'master' into CASSANDRA-6839
More complete testing for collection conditions
Set initial_token for thrift_tests

Conflicts:
	thrift_tests.py
Merge remote-tracking branch 'riptano/master' into CASSANDRA-6839
Merge branch 'master' into python-driver

Conflicts:
	cql_tests.py
	thrift_tests.py