Revert "force struct use for messaging fixes #2"

This reverts commit 9842714.

Author: EricFreeman

src/UnityEventAggregator/EventAggregator.cs

@@ -15,11 +15,9 @@ public static class EventAggregator
         /// </summary>
         /// <typeparam name="T">The type of event being listened for.</typeparam>
         /// <param name="obj"></param>
-        public static void Register<T>(this T obj) where T : struct
+        public static void Register<T>(this object obj)
         {
-            if (!_cache.ContainsKey(typeof(T))) 
-                _cache[typeof(T)] = new List<object>();
-
+            if (!_cache.ContainsKey(typeof(T))) _cache[typeof(T)] = new List<object>();
             _cache[typeof(T)].Add(obj);
         }
 
@@ -28,7 +26,7 @@ public static void Register<T>(this T obj) where T : struct
         /// </summary>
         /// <typeparam name="T">The type of event to no longer listen for.</typeparam>
         /// <param name="obj"></param>
-        public static void UnRegister<T>(this T obj) where T : struct 
+        public static void UnRegister<T>(this object obj)
         {
             if (!_cache.ContainsKey(typeof(T))) return;
             _cache[typeof(T)].Remove(obj);
@@ -65,7 +63,7 @@ public static void UnRegister(object obj, Type listener)
         /// </summary>
         /// <typeparam name="T">The type of event being notified.</typeparam>
         /// <param name="message"></param>
-        public static void SendMessage<T>(T message) where T : struct
+        public static void SendMessage<T>(T message)
         {
             _cache[message.GetType()].Each(x => ((IListener<T>)x).Handle(message));
         }
@@ -74,7 +72,7 @@ public static void SendMessage<T>(T message) where T : struct
         /// Creates the cache for objects that listen to each event
         /// </summary>
         /// <typeparam name="T">Searches through all active GameObjects for those listening for event T and auto registers them.</typeparam>
-        public static void UpdateCache<T>() where T : struct
+        public static void UpdateCache<T>()
         {
             var type = typeof(IListener<T>);
             var list = new List<object>();

src/UnityEventAggregator/IListener.cs

@@ -1,6 +1,6 @@
 namespace UnityEventAggregator
 {
-    public interface IListener<T> where T : struct
+    public interface IListener<T>
     {
         void Handle(T message);
     }