update docstring to match this current implementation

git-svn-id: https://svn.erp5.org/repos/public/erp5/trunk@28086 20353a03-c40f-0410-a6d1-a30d3c3de9de

product/ERP5/Document/Movement.py

@@ -498,7 +498,7 @@ class Movement(XMLObject, Amount):
   def isFrozen(self):
     """
     Returns the frozen status of this movement.
-    a movement in started, stopped, delivered is automatically frozen.
+    a movement in stopped, delivered or cancelled states is automatically frozen.
     If frozen is locally set to '0', we must check for a parent set to '1', in
     which case, we want the children to be frozen as well.