use normal redis if passed options are for standard redis

[henryoswald]

We use redis in an open source project and so need to offer people an easy way to pick between redis and redis sentinel without littering our code with if statments. So I wrote a tiny wrapper https://github.com/sharelatex/redis-sharelatex if there is interest I could put this functionality into this project. Its very basic atm.

[jasonkarns]

I would love this ability. We use redis-sentinel in our dev, qa, stage, and prod environments. But I would love to just be able to run redis standalone locally.