Fixed #113 ApplicationDispatcherUnhandledExceptionHandler was marking handled = true causing the process to keep alive.

@ejsmith We added a process queue statement as the queue could be
processing in the background and won't be awaited for.

I also moved processing queue check down to help prevent any race
conditions.

Author: niemyjski

src/Exceptionless/Queue/DefaultEventQueue.cs

@@ -49,18 +49,18 @@ public Task ProcessAsync() {
         }
 
         public void Process() {
-            if (_processingQueue)
-                return;
-
             if (!_config.Enabled) {
                 _log.Info(typeof(DefaultEventQueue), "Configuration is disabled. The queue will not be processed.");
                 return;
             }
 
-            _log.Trace(typeof(DefaultEventQueue), "Processing queue...");
+            if (_processingQueue)
+                return;
+
             _processingQueue = true;
 
             try {
+                _log.Trace(typeof(DefaultEventQueue), "Processing queue...");
                 _storage.CleanupQueueFiles(_config.GetQueueName(), _config.QueueMaxAge, _config.QueueMaxAttempts);
                 _storage.ReleaseStaleLocks(_config.GetQueueName());
 

src/Platforms/Exceptionless.Windows/ExceptionlessWindowsExtensions.cs

@@ -46,6 +46,7 @@ public static void Unregister(this ExceptionlessClient client) {
             client.SubmittingEvent -= OnSubmittingEvent;
 
             client.ProcessQueue();
+
             if (client.Configuration.SessionsEnabled)
                 client.SubmitSessionEnd();
         }

src/Platforms/Exceptionless.Wpf/ExceptionlessClientExtensions.cs

@@ -57,7 +57,9 @@ public static void RegisterApplicationDispatcherUnhandledExceptionHandler(this E
                     contextData.SetSubmissionMethod("DispatcherUnhandledException");
 
                     args.Exception.ToExceptionless(contextData, client).Submit();
-                    args.Handled = true;
+
+                    // process queue immediately since the app is about to exit.
+                    client.ProcessQueue();
                 };
 
             try {