Add NetDialTimeout to Dialer for per Dialer proxying (i.e. Google's A…

[krolaw]

…pp Engine)

Thoughts?

[krolaw]

dialer := gomail.NewDialer(server, port, login,password)

// Allow appengine to work
dialer.NetDialTimeout = func(network, address string, timeout time.Duration) (net.Conn, error) {
return socket.DialTimeout(ctx, network, address, timeout)
}