Add Ping method.

[andreiavrammsd]

Checks if instances are alive.

errorCollector := make(chan error)
m := memcache.New("/var/run/memcached.sock")

go func() {
	tick := time.NewTicker(time.Second)
	for range tick.C {
		if err := m.Ping(); err != nil {
			errorCollector <- err
		}
	}
}()

go func() {
	for err := range errorCollector {
		fmt.Println(err)
	}
}()

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[andreiavrammsd]

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