Update docs to reflect IMessage->IUserMessage

As changed in 23a0316252

docs/guides/samples/module.cs

@@ -7,7 +7,7 @@ public class Info
 {
     // ~say hello -> hello
     [Command("say"), Description("Echos a message.")]
-    public async Task Say(IMessage msg,
+    public async Task Say(IUserMessage msg,
         [Unparsed, Description("The text to echo")] string echo)
     {
         await msg.Channel.SendMessageAsync(echo);
@@ -20,7 +20,7 @@ public class Sample
 {
     // ~sample square 20 -> 
     [Command("square"), Description("Squares a number.")]
-    public async Task Square(IMessage msg,
+    public async Task Square(IUserMessage msg,
         [Description("The number to square.")] int num)
     {
         await msg.Channel.SendMessageAsync($"{num}^2 = {Math.Pow(num, 2)}");
@@ -34,7 +34,7 @@ public class Sample
     // ~sample whois 96642168176807936 --> Khionu#8708
 	[Command("userinfo"), Description("Returns info about the current user, or the user parameter, if one passed.")]
     [Alias("user", "whois")]
-    public async Task UserInfo(IMessage msg,
+    public async Task UserInfo(IUserMessage msg,
         [Description("The (optional) user to get info for")] IUser user = null)
     {
         var userInfo = user ?? await Program.Client.GetCurrentUserAsync();