Update the code to better reflect recommended style:

Use != instead of <> since <> is documented as "obsolescent".
Use "is" and "is not" when comparing with None or type objects.
diff --git a/Lib/lib-old/packmail.py b/Lib/lib-old/packmail.py
index 4541c51..2a5aa75 100644
--- a/Lib/lib-old/packmail.py
+++ b/Lib/lib-old/packmail.py
@@ -25,7 +25,7 @@
 	while 1:
 		line = fp.readline()
 		if not line: break
-		if line[-1:] <> '\n':
+		if line[-1:] != '\n':
 			line = line + '\n'
 		outfp.write('X' + line)
 	outfp.write('!\n')