[docs] Document TypeReaders, Events, and Joining Audio

docs/guides/samples/joining_audio.cs

@@ -0,0 +1,15 @@
+// Create an IAudioClient, and store it for later use
+private IAudioClient _audio;
+
+// Create a Join command, that will join the parameter or the user's current voice channel
+[Command("join")]
+public async Task JoinChannel(IMessage msg,
+    IVoiceChannel channel = null)
+{
+    // Get the audio channel
+    channel = channel ?? (msg.Author as IGuildUser)?.VoiceChannel;
+    if (channel == null) { await msg.Channel.SendMessageAsync("User must be in a voice channel, or a voice channel must be passed as an argument."); return; }
+
+    // Get the IAudioClient by calling the JoinAsync method
+    _audio = await channel.JoinAsync();
+}

docs/guides/samples/typereader.cs

@@ -0,0 +1,14 @@
+using Discord;
+using Discord.Commands;
+
+public class BooleanTypeReader : TypeReader
+{
+    public override Task<TypeReaderResult> Read(IMessage context, string input)
+    {
+        bool result;
+        if (bool.TryParse(input, out result))
+            return Task.FromResult(TypeReaderResult.FromSuccess(result));
+        
+        return Task.FromResult(TypeReaderResult.FromError(CommandError.ParseFailed, "Input could not be parsed as a boolean."))
+    }
+}