Deleted objects should be considered by the GUI based on events

Current Situation

• A user reports the following scenario:
  1. In the Jobs view: I click on a directory with a single job in the left-side tree : I see the job in the tasks table view.
  2. I drop the job by a rm /.../liv/myjob.job.xml in JS engine.
  3. I still see the job in the task table view (even after several minutes). Expected behavior : I should see "void directory"
  4. I click in the tree on another directory and I click on the original directory again : the task table view is now correct : it says "void directory"
• Consider the linked SourceForge thread

Desired Behavior

• The API fires an event in case that an object is deleted. This event should be considered by the GUI.
• The GUI should not force the user to switch folders in order to refresh the list of available objects