This removes the MetaServers property from node.json to eliminate one
of the four places those addresses are stored on disk. We always use
the values that come through the config (via file, env var or -join arg).
* 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