Added Feedback service test

PushSharp.Tests/ApnsRealTest.cs

@@ -22,7 +22,7 @@ public void APNS_Send_Single ()
                 failed++;
             };
             broker.OnNotificationSucceeded += (notification) => {
-                succeeded++;  
+                succeeded++;
             };
             broker.Start ();
 
@@ -39,6 +39,22 @@ public void APNS_Send_Single ()
             Assert.AreEqual (attempted, succeeded);
             Assert.AreEqual (0, failed);
         }
+
+        [Test]
+        public void APNS_Feedback_Service ()
+        {
+            var config = new ApnsConfiguration (
+                ApnsConfiguration.ApnsServerEnvironment.Sandbox, 
+                Settings.Instance.ApnsCertificateFile, 
+                Settings.Instance.ApnsCertificatePassword);
+
+            var fbs = new FeedbackService (config);
+            fbs.FeedbackReceived += (string deviceToken, DateTime timestamp) => {
+                // Remove the deviceToken from your database
+                // timestamp is the time the token was reported as expired
+            };
+            fbs.Check ();
+        }
     }
 }