Remove useless methods from TodoList.

TodoList.py

@@ -69,10 +69,6 @@ class TodoList(object):
             new_text = todo.source() + ' ' + p_string
             todo.set_text(new_text)
 
-    def set_completed(self, p_number):
-        """ Marks the todo with the given number as complete. """
-        self.todo(p_number).set_completed()
-
     def projects(self):
         """ Returns a set of all projects in this list. """
         result = set()
@@ -91,10 +87,6 @@ class TodoList(object):
 
         return result
 
-    def set_priority(self, p_number, p_priority):
-        """ Sets the priority of the todo with the given number. """
-        self.todo(p_number).set_priority(p_priority)
-
     def view(self, p_sorter, p_filter):
         """
         Constructs a view of the todo list.

test/TodoListTest.py

@@ -107,14 +107,6 @@ class TodoListTester(unittest.TestCase):
 
         self.assertEquals(todo, None)
 
-    def test_completed(self):
-        self.todolist.todo(1).set_completed()
-        today = datetime.date.today().isoformat()
-
-        self.assertTrue(self.todolist.todo(1).is_completed())
-        self.assertEquals(self.todolist.todo(1).source(), \
-            "x " + today + " Foo @Context1 Not@Context +Project1 Not+Project")
-
     def test_string(self):
         # readlines() always ends a string with \n, but join() in str(todolist)
         # doesn't necessarily.