add non-batch consumer
add batch consumer
basic "tests" ... really just examples of usage for now
actually schedule batch merges; get rid of batcher (needlessly complicated)
minor updates to new kafka api
need to use zkStringSerializer
add a bit more room in batch queue
commit position one AFTER last read msg
assorted fixes: (1) start from beginning (2) commit final positions (3) error handling
Merge pull request #1 from quantifind/safe_consumers

Safe kafka consumers that can handle batches