add zremrangebyrank #46
Description
add zremrangebyrank after here to remove some useless data information.
db.multi()
.zremrangebyscore([key, 0, start])
.zcard([key])
.zadd([key, now, now])
.zrange([key, 0, 0])
.zrange([key, -max, -max])
//.zremrangebyrank([key, 0, -(max + 1)])
.pexpire([key, duration])
.exec(function (err, res)