Add comment to Distutil files about requiring 1.5.2 compatibility, as

suggested by PEP 291.

Lib/distutils/cmd.py

@@ -4,6 +4,8 @@ Provides the Command class, the base class for the command classes
 in the distutils.command package.
 """
 
+# This module should be kept compatible with Python 1.5.2.
+
 __revision__ = "$Id$"
 
 import sys, os, string, re