Connect to CASSANDRA_HOST in tests
Astyanax implementation, all specs pass
Added support for nil values, and better value encoding
Updated first and last column values to NULL and empty string
Fixed Pelops case for nil values
Fixed cassandra-jars require
Fixed memory leak caused by batches not being cleaned up on exceptions
Fixed nil-value-handling logic in the Pelops implementation
Making it depend on an external astyanax gem
Don't create keyspaces if they exist
A tiny bit extra test coverage
Reimplemented ColumnFamily#columns_to_h to rely less on JRuby magic

Sometimes #reduce wasn't available on ThriftColumnOrSuperColumnListImpl
Temporarily using local astyanax-jars
Connect to CASSANDRA_HOST in tests