Fixes in 2.0.2:
- Upgrade from 0.4.6 to 2.0.2 directly works
2.0.2 replaces 2.0.1, which contained
- Add support for cluster-level upgrading from etcd 0.4.7 to etcd 2.0.1
- Add cluster-health command to etcdctl
- Add cluster tracking to proxy
- Add a rafttest pkg for raft level failure injection tests
- Change the data directory structure to /{data-dir}/member and /{data-dir}/proxy
- Fix the bug of writing zero length entries message in rafthttp streamer
- Fix a snapshot index bug in store that might lead to data inconsistency