For the user cache, the crypt option rounds are actually the log2 of the number
of rounds. This commits updates the documentation to reflect this.
Original commit: elastic/x-pack-elasticsearch@d3cc2b7f29
* [DOCS] Move security APIs to Elasticsearch Ref
* [DOCS] Update links to security APIs
* [DOCS] Fix link to security APIs
Original commit: elastic/x-pack-elasticsearch@d7a9d3f1ab