(recentf): Added version tag to the defgroup of

(recentf): Added version tag to the defgroup of
recentf.

(recentf-cleanup): Changed to remove excluded file
too.
(recentf-edit-list-action): `recentf-edit-list' checkbox widget
action to select/unselect a file.
(recentf-edit-list): Code cleanup and improvement.
(recentf-open-more-files-action): `recentf-open-more-files' button
widget action to open a file.
(recentf-open-more-files): No more use standard completion but
widgets.
(recentf-more-collection): Deleted.
(recentf-more-history): Deleted.
(recentf-setup-more-completion): Deleted.

(recentf-mode): No more needs that Emacs is running
under a window-system.

(recentf-edit-list): New command to edit the recent
list which allow the user to remove files.
(recentf-edit-selected-items): New global variable, used by
`recentf-edit-list' to hold the list of files to be removed from
the recent list.
(recentf-make-menu-items): Updated to display a "Edit list..."
menu item.  Minor code cleanup.

(recentf-open-more-files): New command to open files
that are not displayed in the menu.
(recentf-more-collection): New global variable holding the set of
permissible completions used by `recentf-open-more-files'.
(recentf-more-history): New global variable holding the history list
used by `recentf-open-more-files' completion.
(recentf-setup-more-completion): New function to setup completion for
`recentf-open-more-files'.
(recentf-make-menu-items): Updated to display a "More..." menu item.

* recentf.el (recentf-menu-action): Doc fixed.

(recentf-menu-filter): Doc updated.
(recentf-update-menu-hook): Allow menu filters to force menu update.
(recentf-make-menu-items): New menu filter handling.
(recentf-make-menu-item): New helper function.
(recentf-menu-elements): New menu handling function.
(recentf-sort-ascending): Updated to new menu filter handling.
(recentf-sort-descending): Updated to new menu filter handling.
(recentf-sort-basenames-ascending): New menu filter function.
(recentf-sort-basenames-descending): New menu filter function.
(recentf-show-basenames): New menu filter function.
(recentf-show-basenames-ascending): New menu filter function.
(recentf-show-basenames-descending): New menu filter function.