ex8.8: About ticker&timer

[miranquil]

I found that you used timer in ex8.8 which was not mentioned in chapter 8.7. So I changed the code to ticker version, which contains this usage in article:

ticker := time.NewTicker(1 * time.Second)
<-ticker.C
ticker.Stop()

Also the exercise requires 10s timeout. I have fixed it too.