Fixed lookup filter for Assignment tasks; Made Assignment.Delivery cascade delete

prs.classes/Entities/Assignment/Assignment.cs

@@ -47,8 +47,11 @@ namespace Comal.Classes
             {
                 if (items == null || !items.Any())
                     return LookupFactory.DefineFilter<Kanban>();
-                return Filter<Kanban>.Where(x => x.Closed).IsEqualTo(DateTime.MinValue).And(x => x.EmployeeLink.ID)
-                    .IsEqualTo(items.First().EmployeeLink.ID);
+                var employeeID = items.First().EmployeeLink.ID;
+                
+                // Open tasks which the employee of this assignment is an observer of.
+                return Filter<Kanban>.Where(x => x.Closed).IsEqualTo(DateTime.MinValue)
+                    .And(x => x.ID).InQuery(Filter<KanbanSubscriber>.Where(x => x.Employee.ID).IsEqualTo(employeeID), x => x.Kanban.ID);
             }
 
             public override Columns<Assignment> DefineFilterColumns()
@@ -115,6 +118,7 @@ namespace Comal.Classes
         public LeaveRequestLink LeaveRequestLink { get; set; }
 
         [NullEditor]
+        [EntityRelationship(DeleteAction.Cascade)]
         public DeliveryLink Delivery { get; set; }
         
         [NullEditor]