Investigate possible migration to github.com/go-redis/redis

[FZambia]

My initial quick measurements for asking stream top showed that we can get ~25% performance boost in Redis benchmarks if migrating from Redigo to github.com/go-redis/redis/v8. But this requires more effort to measure in various scenarios.

github.com/go-redis/redis also supports Redis Cluster and Sentinel so I believe we can migrate related parts too. The good thing is that those are supported by github.com/go-redis/redis natively while currently with redigo we are using 2 additional libs for this: github.com/mna/redisc and github.com/FZambia/sentinel.

Since we have pretty big Redis related code base we may want to migrate step-by-step.

[FZambia]

Or to https://github.com/rueian/rueidis which seems great but need to check whether it fits well our use case (especially PUB/SUB part - we currently have nice re-subscription implementation, hope it's possible to replicate with rueidis).

[FZambia]

Migrated to rueidis in #262 - next days I'll proceed with release and blog post about the migration. The draft of blog post is here: centrifugal/centrifugal.dev#18

[FZambia]

v0.28.0 contains new Redis Engine implementation based on https://github.com/rueian/rueidis