add UPDATING patch

mutt-1.5.21-updating.patch

@@ -0,0 +1,24 @@
+# HG changeset patch
+# User Brendan Cully <brendan@kublai.com>
+# Date 1284573211 25200
+# Branch HEAD
+# Node ID bd0afbb35c65a9e80c55636e214ca85890554ce1
+# Parent  b42be44bb41a2bca21289aa10a490f58e6bbf044
+Belatedly update UPDATING
+
+diff -r b42be44bb41a -r bd0afbb35c65 UPDATING
+--- a/UPDATING	Wed Sep 15 10:21:04 2010 -0700
++++ b/UPDATING	Wed Sep 15 10:53:31 2010 -0700
+@@ -4,8 +4,11 @@
+ The keys used are:
+   !: modified feature, -: deleted feature, +: new feature
+ 
+-hg tip:
++1.5.21 (2010-09-15):
+ 
++  + $mail_check_recent controls whether all unread mail or only new mail
++    since the last mailbox visit will be reported as new
++  + %D format expando for $folder_format
+   ! $thorough_search defaults to yes
+   + imap-logout-all closes all open IMAP connections
+   ! header/body cache paths are always UTF-8