[DOCS] Add how-to guide for time series data

[jrodewig]

Adds a how-to guide for using Elasticsearch for time series data. Covers:

• Configuring data tiers
• Setting up SLM and a snapshot repository
• Setting up ILM
• Creating a data stream and a matching template
• Searching time series data with runtime fields and async search

It reuses several parts from the set up a data stream tutorial.

Preview

https://elasticsearch_71195.docs-preview.app.elstc.co/guide/en/elasticsearch/reference/master/use-elasticsearch-for-time-series-data.html

[elasticmachine]

Pinging @elastic/es-core-features (Team:Core/Features)

[elasticmachine]

Pinging @elastic/es-distributed (Team:Distributed)

[elasticmachine]

Pinging @elastic/es-docs (Team:Docs)

[jrodewig]

@elasticmachine update branch

[dakrone]

I left some comments, thanks for working on this @jrodewig!

I was thinking, do you think it's worth calling out the license level required for the example ILM policy?

[jrodewig]

Thanks for the review and suggestions @dakrone. I've incorporated your feedback with the exception of the subscription levels.

The Elastic docs guild has talked about this a bit, and we agreed to avoid including subscription levels in the docs. The expectation is that these levels could change quickly, and we don't want to be in a situation where our docs conflict with elastic.co/subscriptions, which we treat as the sole source of truth.

Thanks again! Let me know if you have any other feedback.

[ywelsch]

I've left two small comments, related to searchable snapshot integration. Overall I think this guide is very useful.

[jrodewig]

Thanks for the review @ywelsch. I made some changes to the snapshot repository section to address your feedback. Please let me know if you have any other thoughts!

[ywelsch]

LGTM

[dakrone]

LGTM, thanks @jrodewig!

[jrodewig]

Thanks @dakrone @ywelsch!