Member read timestamp shouldn't be updated during heartbeat when its connection is not alive. Cleaned up heart-beater task.
Cluster service refactor and cleanup (as a preparation step for future refactor)
More cluster join cleanup and improvements. refactored join and split-brain tests. Moved simple join tests to quick profile.
Merge pull request #3028 from mdogan/fix/3.3/heartbeat

Member read timestamp shouldn't be updated during heartbeat when its connection is not alive