func (n DefaultNotifier) OnStop(gid string) {
	log.Printf("on stop: %v", gid)
}
OnPause implements Notifier interface.
package aria2go
import (
	"log"
)
type Notifier interface {
	OnStart(gid string)
	OnPause(gid string)
	OnStop(gid string)
	OnComplete(gid string)
	OnError(gid string)
}
type DefaultNotifier struct{}
func newDefaultNotifier() Notifier {
	return DefaultNotifier{}
}
func (n DefaultNotifier) OnStart(gid string) {
	log.Printf("on start %v", gid)
}
func (n DefaultNotifier) OnPause(gid string) {
	log.Printf("on pause: %v", gid)
}