Remove copyright notices from gencodec.py output.

The script was originally used to create the initial set of
codecs (and these were (c) CNRI). While the script itself still
is (c) CNRI, the output certainly isn't anymore.
diff --git a/Tools/scripts/gencodec.py b/Tools/scripts/gencodec.py
index fdaa8fe..75337d6 100644
--- a/Tools/scripts/gencodec.py
+++ b/Tools/scripts/gencodec.py
@@ -154,11 +154,6 @@
         '''\
 """ Python Character Mapping Codec generated from '%s' with gencodec.py.
 
-Written by Marc-Andre Lemburg (mal@lemburg.com).
-
-(c) Copyright CNRI, All Rights Reserved. NO WARRANTY.
-(c) Copyright 2000 Guido van Rossum.
-
 """#"
 
 import codecs