Support for OSS Cluster

[filipecosta90]

The current edge version of RedisTimeSeries is suited for working with an OSS Cluster topology in the following manner:

• on single key commands like any other command
• on commands that require multi-key gatter/aggregation/filtering ( like TS.MRANGE, TS.MGET, TS.MREVRANGE,... ) when used together with RedisGears ( Gears integration PR Gears integration (rebased) RedisTimeSeries#653 ).

Even though still not released, we should start embracing cluster-ready ( or topology agnostic ) clients.

[filipecosta90]

reminder that I'm to provide the scripts for easily testing this. need 1 day to do it.