fix close socket

[k0st1a]

When i use method ezmq:close(Socket), some processes are still living.

[RoadRunnr]

I think it would be better to link the transport from the handle_cast deliver_connect case in ezmq.erl. That would mirror the logic of deliver_accept.

e.g.:

handle_cast({deliver_connect, Transport, {ok, RemoteId}}, State) ->
    link(Transport),
    State1 = transports_activate(Transport, RemoteId, State),
    State2 = send_queue_run(State1),
    {noreply, State2};

Or even better, move the link/unlink logic into transports_activate/transports_deactivate.

And you should open pull requests for ezmq against the ZeroMQ project repo