improvements to scheduler,

better parallelism on RSS fetch

NzbDrone.Common/Messaging/CommandCompletedEvent.cs

@@ -0,0 +1,12 @@
+namespace NzbDrone.Common.Messaging
+{
+    public class CommandCompletedEvent : IEvent
+    {
+        public ICommand Command { get; private set; }
+
+        public CommandCompletedEvent(ICommand command)
+        {
+            Command = command;
+        }
+    }
+}