Add configs for creating the admin room and granting first user.

Signed-off-by: Jason Volk <jason@zemos.net>

docker/Dockerfile.complement

@@ -75,6 +75,7 @@ COPY <<EOF complement.toml
     allow_public_room_directory_over_federation = true
     allow_public_room_directory_without_auth = true
     allow_registration = true
+    create_admin_room = false
     database_path = "/database"
     dns_attempts = 20
     dns_timeout = 60