Possible fix for #5437. meta.Client.RetentionPolicy acquired a read-lock and
then called Database which called data() which acquired a read-lock again.
If a write lock was taken between these two read-locks (likely by Authenticate),
the write-lock would block, and the second read-lock would also block
causing a dead-lock.
* Improve the ping endpoint so that it can optionally check for leader agreement across all meta servers
* Add Ping method to the meta client
* Fix ClusterID tests
* Remove WaitForLeader from meta client and remove unnecessary references to it
* Updated CreateShardGroup to not return an error if it already exists so it's idempotent
* Removed old test making sure you can't delete the default RP. You can delete it now, there was no reason to disallow it.
* Wired up the UpdateRetentionPolicy functionality
* increase sleep on error in client exec in case a server went down so we don't max out retries before a new leader gets elected
* update and add close logic to service, handler, raft state, and the client
* Add dir, hostname, and bind address to top level config since it applies to services other than meta
* Add enabled flags to example toml for data and meta services
* Wire up add/remove raft peers and meta servers to meta service
* Update DROP SERVER to be either DROP META SERVER or DROP DATA SERVER
* Bring over statement executor from old meta package
* Start meta service client implementation
* Update meta service test to use the client
* Wire up node ID/meta server storage information
Ben Johnson
David Norton
Seif Lotfy
Jason Wilder
Paul Dix
Cory LaNou