issue #359 - ASSIGNED: Implement FilterGraph EMF/GMF model
http://agalaldev.info/dev/mantis/view.php?id=359

- Removing Filter Configuration EMF Object from being returned when calling getChildren() for a FilterInstance, this prevents "Configuration" element from being listed under FilterInstance in EMF tree editor
- Make PortInstance extend identifiable, in order to have a name
- Generated EMF Editor now uses the Editing domain managed by EMFUtils
- Port instances are updated when the filter type of a FilterInstance is changed, references to deleted objects are handled "EcoreUtils.delete()"