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.
OK, there's a method in the producer
```
    @Override
    public List<PartitionInfo> partitionsFor(String topic) {
        waitOnMetadata(topic, this.metadataFetchTimeoutMs);
        return this.metadata.fetch().partitionsForTopic(topic);
    }
````