#2622 Import errors in email.message, from a py2app standalone application.

Patch by Mads Kiilerich, Reviewed by Barry Warsaw.
diff --git a/Lib/email/message.py b/Lib/email/message.py
index 23cedf6..129f4ba 100644
--- a/Lib/email/message.py
+++ b/Lib/email/message.py
@@ -129,7 +129,7 @@
         "From ".  For more flexibility, use the flatten() method of a
         Generator instance.
         """
-        from email.Generator import Generator
+        from email.generator import Generator
         fp = StringIO()
         g = Generator(fp)
         g.flatten(self, unixfrom=unixfrom)
@@ -787,4 +787,4 @@
         return [part.get_content_charset(failobj) for part in self.walk()]
 
     # I.e. def walk(self): ...
-    from email.Iterators import walk
+    from email.iterators import walk