add specs2 and offsetmanager test
Merge branch 'at_least_once' into add_test
change specs2 version
add offsetManagerSpec
Merge remote-tracking branch 'remotes/origin/at_least_once' into add_test
close thread and change no message log to debug level
KafkaCheckpointManager uses the low level Kafka consumer and consumes only once
Merge remote branch 'upstream/master' into add_test
Merge remote branch 'origin/at_least_once' into add_test
make specs2 work
transaction interface refactor
Merge branch 'add_test' of https://github.com/manuzhang/gearpump into add_test
refactor transaction interface
transaction interface refactor
refactor filter interface
remove tests for this branch
add TimeExtractor and change api
dedicate a thread to fetch and consolidate all messages from a broker
fix message iterator bugs and change configs
fix message iterator and checkpoint bugs