code: func NewDockerClient() (client *docker.Client, err error) {
  	endpoint := viper.GetString("vm.endpoint")
  	tlsenabled := viper.GetBool("vm.docker.tls.enabled")
  	if tlsenabled {
  		cert := config.GetPath("vm.docker.tls.cert.file")
  		key := config.GetPath("vm.docker.tls.key.file")
  		ca := config.GetPath("vm.docker.tls.ca.file")
  		client, err = docker.NewTLSClient(endpoint, cert, key, ca)
  	} else {
  		client, err = docker.NewClient(endpoint)
  	}
  	return
  }
docs: //NewDockerClient creates a docker client