returning `Connection`

Currently `remote_repl` returns a connection and writes to the global `_repl_client_connection`.

And `connect_repl` doesn't return a connection but also writes to the global `_repl_client_connection`.

I find this behavior inconsistent. Is it necessary that `connect_repl` returns the `ReplMaker` `prompt` ?
In any case, I think it would be nice to also return the `Connection`.
This way the client can always have a way of closing the connection. (without having to access the global `_repl_client_connection`)
Aside from that, this could also enable handling multiple connections.