moved vpnConnection to separate thread

- added tabbar blocking when installing/removing containers

client/ui/controllers/pageController.h

@@ -88,6 +88,7 @@ signals:
     void showNotificationMessage(const QString &message);
 
     void showBusyIndicator(bool visible);
+    void enableTabBar(bool enabled);
 
     void hideMainWindow();
     void raiseMainWindow();