add test codes for ImplES

* src/main/java/com/ktcloudware/kafka2es/Kafka2Es.java (modified)
* src/main/java/com/ktcloudware/kafka2es/KafkaProducer.java (added)
* src/main/java/com/ktcloudware/kafka2es/kafkastream/KafkaStreamJobImplES.java (modified)
* src/test/java/com/ktcloudware/kafka2es/kafkastream/KafkaStreamJobImplESTest.java (added)
Merge branch 'master' of https://github.com/yoodoc/kaf2es