add department sql join query, alter person model to fit department data

Form1.cs

@@ -41,7 +41,7 @@ namespace it_projekt
             }
             foreach (Person person in db.Persons)
             {
-                this.dataGrid.Rows.Add(person.Id, person.Firstname, person.Lastname, person.CreationDate, false);
+                this.dataGrid.Rows.Add(person.Id, person.Firstname, person.Lastname, person.department_short, person.department_long, person.CreationDate, false);
             }
         }