Feature/graylog logger
- log to graylog via TCP, tbd...
- GrayLogger module extends winston.transport
- configurable: level, source, host, port, path
- see readme for example usage
- will log: json: source, message, severity
- if msg is json, it will be logged as separate fields
- example:
message: Authentication: userdata loaded severity: info source: nano-hp-win8 timestamp:2017-07-07T12:16:44.567Z