Add provision command to bootstrap metadata store and write initial NodesConfiguration

[tillrohrmann]

restatectl cluster provision --address <node-address> signals this node to bootstrap the metadata store if it is running an embedded metadata store and writing an initial NodesConfiguration, PartitionTable and LogsConfiguration with the appropriate cluster configuration. It is the user's responsibility to retry this command if it fails and to never invoke for different nodes. If the user does it, then he might end up with multiple clusters.

[tillrohrmann]

This issue depends on #2411 because we need to have a server running on which we can receive the provision command.