To be able to label incoming tor connections as different from normal localhost connections in e.g. `getpeerinfo` and the peers list in the GUI it'd be useful to have them connect on an alternative local-only port. Or even better, a UNIX socket.

For manually set-up hidden services this would have to be configured manually and could add a `hsport` option or such. The external port would still appear as `XXXXXXXXX.onion:8333`, however internally it would redirect to a that port.

In the case of `torcontrol` this would be easy to set up automatically. It could add a new (localhost) binding port automatically and this code would have to be changed:
- https://github.com/bitcoin/bitcoin/blob/master/src/torcontrol.cpp#L441
- https://github.com/bitcoin/bitcoin/blob/master/src/torcontrol.cpp#L477

{
    if (b_conn)
        Disconnect();
    
    struct sockaddr_storage connect_to_addr;
    int connect_to_addrlen = sizeof(connect_to_addr);
    if (evutil_parse_sockaddr_port(target.c_str(),
        (struct sockaddr*)&connect_to_addr, &connect_to_addrlen)<0) {
        LogPrintf("tor: Error parsing socket address %s\n", target);
        return false;
    }
    
    b_conn = bufferevent_socket_new(base, -1, BEV_OPT_CLOSE_ON_FREE);
    if (!b_conn)
        return false;
    bufferevent_setcb(b_conn, TorControlConnection::readcb, nullptr, TorControlConnection::eventcb, this);
    bufferevent_enable(b_conn, EV_READ|EV_WRITE);
    this->connected = _connected;
    this->disconnected = _disconnected;
    
    if (bufferevent_socket_connect(b_conn, (struct sockaddr*)&connect_to_addr, connect_to_addrlen) < 0) {
        LogPrintf("tor: Error connecting to address %s\n", target);
        return false;
    }
    return true;
}
void TorControlConnection::Disconnect()