We should ignore --token and --server if the managed database is initialized,
just like we ignore --cluster-init. If the user wants to join a new
cluster, or rejoin a cluster after --cluster-reset, they need to delete
the database. This a cleaner way to prevent deadlocking on quorum loss,
and removes the requirement that the target of the --server argument
must be online before already joined nodes can start.
Signed-off-by: Brad Davidson <brad.davidson@rancher.com>