Added support for reaction 'me' field

src/Discord.Net.Core/Entities/Messages/IUserMessage.cs

@@ -14,7 +14,7 @@ namespace Discord
         Task UnpinAsync(RequestOptions options = null);
 
         /// <summary> Returns all reactions included in this message. </summary>
-        IReadOnlyDictionary<Emoji, int> Reactions { get; }
+        IReadOnlyDictionary<Emoji, ReactionMetadata> Reactions { get; }
 
         /// <summary> Adds a reaction to this message. </summary>
         Task AddReactionAsync(Emoji emoji, RequestOptions options = null);

src/Discord.Net.Core/Entities/Messages/ReactionMetadata.cs

@@ -0,0 +1,11 @@
+namespace Discord
+{
+    public struct ReactionMetadata
+    {
+        /// <summary> Gets the number of reactions </summary>
+        public int ReactionCount { get; internal set; }
+
+        /// <summary> Returns true if the current user has used this reaction </summary>
+        public bool IsMe { get; internal set; }
+    }
+}