#14925: email now registers a defect for missing header/body separator.

This patch also deprecates the MalformedHeaderDefect.  My best guess is that
this defect was rendered obsolete by a refactoring of the parser, and the
corresponding defect for the new parser (which this patch introduces) was
overlooked.
diff --git a/Misc/NEWS b/Misc/NEWS
index 512783a..e8171ac 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -49,6 +49,10 @@
 Library
 -------
 
+- Issue #14925: email now registers a defect when the parser decides that there
+  is a missing header/body separator line.  MalformedHeaderDefect, which the
+  existing code would never actually generate, is deprecated.
+
 - Issue #10365: File open dialog now works instead of crashing
   even when parent window is closed. Patch by Roger Serwy.