More tests for reconfiguraion.
Made ack_epoch proposed_epoch file readable.
Remove enum in Transaction.
Cleanup logging.
Merge pull request #116 from EasonLiao/plain_epoch

ack_epoch and proposed_epoch are not human readable
Merge pull request #122 from EasonLiao/clean_log

log message cleanup
Merge pull request #129 from EasonLiao/more_tests

More tests for reconfiguraion.
Merge pull request #130 from EasonLiao/remove_enum

Remove enum in Transaction.
netty transport: add ssl support.
netty transport: set access levels of inner classes properly.
Merge pull request #132 from m1ch1/ssl

netty transport: add ssl support.
Change the cluster configuration of AckProcessor at correct time.
Fixed the bug and more logging messages for AckProcessor.