Added a link to the repo in the help

Just in case someone needs assistance, so that they can find me when i
relaunch nadeko, since i will be firing up NadekoBot again and on a much
better server tomorrow or day after tomorrow.

NadekoBot/Commands/HelpCommand.cs

@@ -10,7 +10,7 @@ namespace NadekoBot
         {
             return async e =>
                 {
-                    string helpstr = "";
+                    string helpstr = "Official repo: https://github.com/Kwoth/NadekoBot/"+Environment.NewLine;
                     foreach (var com in client.Commands().AllCommands)
                     {
                         helpstr += "&###**#" + com.Category + "#**\n";