New: Rebuilt Completed/Failed download handling from scratch

src/NzbDrone.Core/DecisionEngine/Decision.cs

@@ -7,12 +7,14 @@ namespace NzbDrone.Core.DecisionEngine
         public Boolean Accepted { get; private set; }
         public String Reason { get; private set; }
 
+        private static readonly Decision AcceptDecision = new Decision { Accepted = true };
+        private Decision()
+        {
+        }
+
         public static Decision Accept()
         {
-            return new Decision
-            {
-                Accepted = true
-            };
+            return AcceptDecision;
         }
 
         public static Decision Reject(String reason, params object[] args)