Made the main thread wait for the SIPApplication thread at exit

blink/__init__.py

@@ -57,6 +57,7 @@ class Blink(QApplication):
         self.exec_()
         self.update_manager.shutdown()
         self.application.stop()
+        self.application.thread.join()
 
     def customEvent(self, event):
         handler = getattr(self, '_EH_%s' % event.name, Null)