Cleaned up several classes

src/Discord.Net.Audio/VoiceDisconnectedEventArgs.cs

@@ -0,0 +1,15 @@
+using System;
+
+namespace Discord
+{
+    public class VoiceDisconnectedEventArgs : DisconnectedEventArgs
+    {
+        public ulong ServerId { get; }
+
+        public VoiceDisconnectedEventArgs(ulong serverId, bool wasUnexpected, Exception ex)
+            : base(wasUnexpected, ex)
+        {
+            ServerId = serverId;
+        }
+    }
+}