Few updates to mailing library for .NET Micro Framework

.NET Micro Framework has good enough support for TCP/IP, so why not to send e-mails from tiny devices? Because the SmtpClient class is missing. Hmmm, is it hard to implement it? Well, a bit but it's not impossible.

Last days I've spend writing echo server and client application for tcp and udp protocols. Echo is very useful for developers and network administrators.