added KafkaV2 sink using new kafka producer in 0.8.2-SNAPSHOT

@metacret here is the pull request that we discussed.  Please see suro-server/conf/sink_using_kafkaV2.json for the configuration syntax.
In the new producer, partitioning logic with the key is murmur32 hashing but the old one's hash partitioning logic is key.hashCode(). So, we need to create ProducerRecord with the partitioning key as keyedMessage.getKey().hashCode() % (number of partition) for the backward compatibility. But how can we get a number of partition in advance?