This commit removes the FAILED state for the IndexAuditTrail so that we always try to keep starting
the service. Previously, on any exception during startup we moved to a failed state and never tried
to start again. The users only option was to restart the node. This was problematic in the case of
large clusters as there could be common timeouts of cluster state listeners that would cause the
startup of this service to fail.
Additionally, the logic in the IndexAuditTrail to update the template on the current cluster has
been removed and replaced with the use of the TemplateUpgradeService. However, we still need to
maintain the ability to determine if a template on a remote cluster should be PUT. To avoid always
PUTing the template, the version field has been added so it only needs to be PUT once on upgrade.
Finally, the default queue size has been increased as this is another common issue that users hit
with high traffic clusters.
relates elastic/x-pack-elasticsearch#2658
Original commit: elastic/x-pack-elasticsearch@27e2ce7223
4f65d9b527