GUACAMOLE-598: Abort rendering of pages if critical data fails to load (data without which the page is non-functional).

guacamole/src/main/webapp/app/manage/controllers/manageConnectionGroupController.js

@@ -245,7 +245,7 @@ angular.module('manage').controller('manageConnectionGroupController', ['$scope'
                     PermissionSet.hasConnectionPermission,
                     identifier);
 
-    }, requestService.WARN);
+    }, requestService.DIE);
 
     /**
      * Cancels all pending edits, returning to the main list of connections