This change makes the etcd package compatible with the existing Go
ecosystem for module versioning.
Used this tool to update package imports:
https://github.com/KSubedi/gomove
- Add/Document "logger" to support structured logging.
- This makes functional tests run easier, since zap logger
provides built-in log redirect to files.
- "etcd --logger-option=zap" to enable structured logging.
- Current "capnslog" will still be used as "default".
- We may switch the default or deprecate "capnslog" in v3.5.
- Either way, will clearly be documented.
Signed-off-by: Gyuho Lee <gyuhox@gmail.com>