upgraded to autofac 3. created nancy only mode for nzbdrone.exe /n

NzbDrone.Common/EnsureThat/ExceptionFactory.cs

@@ -0,0 +1,22 @@
+using System;
+using NLog;
+
+namespace NzbDrone.Common.EnsureThat
+{
+    internal static class ExceptionFactory
+    {
+        private static readonly Logger Logger = LogManager.GetLogger("ArgumentValidator");
+
+        internal static ArgumentException CreateForParamValidation(string paramName, string message)
+        {
+            Logger.Warn(message);
+            return new ArgumentException(message, paramName);
+        }
+
+        internal static ArgumentNullException CreateForParamNullValidation(string paramName, string message)
+        {
+            Logger.Warn(message);
+            return new ArgumentNullException(paramName, message);
+        }
+    }
+}