applied HADOOP-10641
ZkConnection allows to retry operation in safe manner, uses async zk interface.
listeners and minor cleanup
create and delete zk operations
simplified event handling
minor ZkConnection fixes. InterruptedException now exposed in API.
CoordinationEngine should not dictate start/stop api.
using Protobuf for storing GSN in zk
Refactored version of CE
keep logging minimal, moving them to TRACE level
batch GSN updates option.
small cleanup
removed mockit until it really be needed.
ZkConnection: using ListenableFutures. Using separate ExecutorServices (by default same thread) to resubmit operations.
extracted ZKAgreementsStorage, buckets implemented.
format pom.xml and add mockito
ZkAgreementStorage tests
adding precheck for submitProposal
fixing tests for new buckets system (number of agreements can be greate then expected)
get rid of async proposals, zk already does that in async fashion