Add missing Time Series aggregator types

[burmisov]

Just noticed that some of the aggregator types are missing from the Aggregation selector.

Used this as a reference: https://redis.io/commands/ts.range/ Descriptions are taken straight from the official TS.RANGE command doc.

I've examined the code a bit and it seems like this is the only place that needs to be changed, but not 100% sure...

Thanks for an awesome plugin

[mikhail-vl]

@burmisov Thanks for contribution. I have not tested it, but looks good to me.

I will let Redis team to follow-up.

[mipapo]

@burmisov How hard would it be to add the GROUPBY https://redis.io/commands/ts.mrange/?