Added missing ToString and DebuggerDisplays

src/Discord.Net.Rest/Entities/Messages/RestMessage.cs

@@ -1,13 +1,11 @@
 using System;
 using System.Collections.Generic;
 using System.Collections.Immutable;
-using System.Diagnostics;
 using System.Threading.Tasks;
 using Model = Discord.API.Message;
 
 namespace Discord.Rest
 {
-    [DebuggerDisplay(@"{DebuggerDisplay,nq}")]
     public abstract class RestMessage : RestEntity<ulong>, IMessage, IUpdateable
     {
         private long _timestampTicks;
@@ -56,6 +54,8 @@ namespace Discord.Rest
             Update(model);
         }
 
+        public override string ToString() => Content;
+
         MessageType IMessage.Type => MessageType.Default;
     }
 }