now you can call 
`hub, err := registry.New(*registryURL, *username, *password, log.Infof)`
so all the logs will go through your favorit logger, like logrus.
Ex code : 

```
func main() {
	log.Out = os.Stdout
	log.Formatter = new(logrus.JSONFormatter)
	log.Level = logrus.DebugLevel

	flag.Parse()
	hub, err := registry.New(*registryURL, *username, *password, log.Infof)
	if err != nil {
		log.Fatalf("error connecting to hub, %v", err)
	}
...
```

Ypu can switch `log.Level = logrus.DebugLevel` to `log.Level = logrus.WarnLevel` to disable logging

https://github.com/heroku/docker-registry-client/pull/30/files