Go redis connection pool

Redisgo can use the connection pool:

	pool = &redis.Pool{
		Dial: func() (conn redis.Conn, e error) {
			return redis.Dial("tcp","192.168.50.131:6379")
		},
		MaxIdle:3,
		MaxActive:5,
		IdleTimeout:240 * time.Second,
	}

　Use of connection pool:

	conn := pool.Get()
	defer conn.Close()
	conn.Do("set","addr","wuhan")