Kafka 0.8 Support for SummingBird

Don't merge yet. Work in progress

- [x] Create Kafka 08 module
- [x] Test SummingBird with Kafka 08 spout
I don't think forceFromStart should always be set to true. The optional parameter forceStartOffsetTime determines the start point and defaults to -1 (LatestTime) . It isn't related to the stateUpdateIntervalMs.

See: https://github.com/kafka-dev/kafka/blob/master/core/src/main/scala/kafka/api/OffsetRequest.scala#L28