code: func put(db keyval.ProtoBroker, data []string) {
  	c := &phonebook.Contact{Name: data[0], Company: data[1], Phonenumber: data[2]}
  
  	key := phonebook.EtcdContactPath(c)
  
  	err := db.Put(key, c)
  	if err != nil {
  		log.Fatal(err)
  	}
  
  	fmt.Println("Saved:", key)
  }
docs: // put saves single entry