Tests for CASSANDRA-6839
Add test coverage for IN operator on column conditions
test skeleton implemented
working Json export/import
Implemented json_tools dtest
refactored to remove unnecessary code
pushed file i/o to CCM
moved file i/o back into the test
Accept null values in element access column conditions

Done for CASSANDRA-6839
user types can't contain counters
Merge branch 'master' into more_user_types_tests
test for user type as clustering col
pep8 and unused imports
Old thrift tests from C* source, refactored to become a dtest.
Another attempting at fixing CASSANDRA-7599
Remove cruft
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test for 7730
Merge branch 'master' of github.com:riptano/cassandra-dtest
Merge pull request #82 from riptano/7598

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