bug#16170: Customizable log-edit commit messages

[Juri Linkov <juri@jurta.org>]

> Currently the commit message is hard-coded that might be unsuitable
> to other projects with different conventions.  This patch leaves the
> current default unchanged, and moves it to a separate function,
> so a set of messages could by easily configured in `log-edit-hook'.
> Adding `save-excursion' to `log-edit-insert-cvs-template' was
> necessary to not move point set by `message-position-point' in
> `log-edit-insert-message-template'.

This is a useful addition to accompany log-edit-insert-filenames
to insert the names of files that don't require ChangeLog entry,
but should be mentioned in the commit message:

=== modified file 'lisp/vc/log-edit.el'
--- lisp/vc/log-edit.el	2013-12-04 00:37:33 +0000
+++ lisp/vc/log-edit.el	2013-12-18 23:52:35 +0000
@@ -137,6 +137,7 @@
 			 log-edit-insert-cvs-template
 			 log-edit-insert-changelog
 			 log-edit-insert-filenames
+                        log-edit-insert-filenames-without-changelog
 			 log-edit-show-files)))
 
 (defcustom log-edit-mode-hook (if (boundp 'vc-log-mode-hook) vc-log-mode-hook)
@@ -664,6 +666,21 @@
   (insert "Affected files:  \n"
           (mapconcat 'identity (log-edit-files) "  \n")))
 
+(defun log-edit-insert-filenames-without-changelog ()
+  "Insert the list of files that have no ChangeLog message."
+  (interactive)
+  (let ((files
+	 (delq nil
+	       (mapcar
+		(lambda (file)
+		  (unless (or (cdr-safe (log-edit-changelog-entries file))
+			      (equal (file-name-nondirectory file) "ChangeLog"))
+		    file))
+		(log-edit-files)))))
+    (when files
+      (goto-char (point-max))
+      (insert (mapconcat 'identity files ", ") ": "))))
+
 (defun log-edit-add-to-changelog ()
   "Insert this log message into the appropriate ChangeLog file."
   (interactive)