org-agenda: Fix order when writing to an ".org" file

* lisp/org-agenda.el (org-agenda-write): Write headings in proper
  order.

`org-paste-subtree' leaves point before inserted text, so there is no
need to reverse contents.

http://permalink.gmane.org/gmane.emacs.orgmode/89867

lisp/org-agenda.el

@@ -3352,7 +3352,7 @@ If AGENDA-BUFFER-NAME, use this as the buffer name for the agenda to write."
 			   content)))
 		 (find-file file)
 		 (erase-buffer)
-		 (mapcar (lambda (s) (org-paste-subtree 1 s)) (reverse content))
+		 (dolist (s content) (org-paste-subtree 1 s))
 		 (write-file file)
 		 (kill-buffer (current-buffer))
 		 (message "Org file written to %s" file)))