Add support of pulsar-kafka-adapter for kafka-0.8 api (#4797)

* Add support pulsar-kafka-adapter for kafka-0.8 api

clean up pulsar-kafka adapter

add tests

add low level consumer

add simple consumer

corrected pulsar-client-kafka_0_8

fix the module name

add batch and partitioned-topic support

fix headers

add getOffset api support

added pulsarOffset request/response

 clean up

* add pulsar-kafka integration test

* use earliestTime offset

* add default serializer/de
36 files changed