Add data_stream fields to ECS

[ruflin]

The fields data_stream.type, data_stream.dataset and data_stream.namespace are used as the foundation of the new indexing strategy. These should also be added to ECS.

[elasticmachine]

Pinging @elastic/ingest-management (Team:Ingest Management)

[ph]

@webmat Is that something that you could take in your team?

[webmat]

This is already in progress via the RFC process here elastic/ecs#980. When this RFC reaches stage 3 is when the fields will first appear officially in the ECS docs & everywhere.

[ph]

Oh wow thanks @roncohen

[ebeahan]

The data_stream.* fields RFC has advanced to finished, and its changes are being implemented to the schema in elastic/ecs#1307.

[botelastic]

Hi! We just realized that we haven't looked into this issue in a while. We're sorry! We're labeling this issue as Stale to make it hit our filters and make sure we get back to it as soon as possible. In the meantime, it'd be extremely helpful if you could take a look at it as well and confirm its relevance. A simple comment with a nice emoji will be enough :+1. Thank you for your contribution!