This commit uses the index settings version so that a follower can
replicate index settings changes as needed from the leader.
Co-authored-by: Martijn van Groningen <martijn.v.groningen@gmail.com>
* Changed the auto follow stats to also include follow stats.
* Renamed the auto follow stats api to stats api and changed its url path
from `/_ccr/auto_follow/stats` `/_ccr/stats`.
* Removed `/_ccr/stats` url path for the follow stats api, which makes
the index parameter a required parameter.
* Fixed docs.
This commit is our first introduction to cross-cluster replication
docs. In this commit, we introduce the cross-cluster replication API
docs. We also add skelton docs for additional content that will be added
in a series of follow-up commits.