Change note on StopIteration and SystemExit on how they now have stricter

inheritance thanks to no longer inheriting from Exception.

pep-0348.txt

@@ -85,8 +85,8 @@ New Hierarchy
     +-- SystemError (stricter inheritance)
  +-- ControlFlowException (new)
     +-- GeneratorExit (defined in PEP 342 [PEP342]_)
-    +-- StopIteration (broader inheritance)
+    +-- StopIteration (stricter inheritance)
-    +-- SystemExit (broader inheritance)
+    +-- SystemExit (stricter inheritance)
  +-- Exception
     +-- StandardError
 	+-- ArithmeticError
@@ -273,6 +273,15 @@ entirely separate exception that will not be caught by a bare ``except``
 clause.
 
 
+StopIteration and SystemExit
+''''''''''''''''''''''''''''
+
+Inherit from ControlFlowException instead of Exception.
+
+By having these exceptions no longer inherit from Exception they will not be
+accidentally caught by a bare ``except`` clause.
+
+
 NotImplementedError
 '''''''''''''''''''