Extend BrandInfo setting

Brand Information tells the server what client is being used to connect
to the server, possible values are the following:

- none (do not tell anything)
- vanilla (tells that you are using MC vanilla)
- mcc (tell that you are using MCC + version)

This will usually not do anything unless plugins developers use this
information for developing some MCC interoperability eg more chat
interactions instead of using GUIs. This could also be used to block
third party clients, that's why brand information can be disabled or
changed to vanilla.

MinecraftClient/McTcpClient.cs

@@ -120,6 +120,9 @@ namespace MinecraftClient
                 {
                     if (handler.Login())
                     {
+                        if (!String.IsNullOrWhiteSpace(Settings.BrandInfo))
+                            handler.SendBrandInfo(Settings.BrandInfo.Trim());
+
                         if (singlecommand)
                         {
                             handler.SendChatMessage(command);