[Proposal] Allow redislock to compatible with multi versions of go-redis #77

Currently, redislock only depends on the Redis EVAL/EVALSHA command
but directly introduces the go-redis/v9 scripter as the RedisClient interface.
And make it incompatible with other versions of the Redis client like go-redis/v8.

I think we can avoid binding to any versions by moving the scripter outside the go-redis.

I will be happy to support this if it sounds good to you.

related issue: #48