* riece.el: Add autoload setting for derived-mode-class.

* riece.el: Add autoload setting for derived-mode-class.
(riece-shrink-buffer-idle-timer): New variable.
(riece): Set idle timer to shrink channel buffers.
(riece-shrink-buffer): New function.

* riece-xemacs.el (riece-overlays-in): New function.
(riece-delete-overlay): New alias.
(riece-kill-all-overlays): New function.

* riece-server.el (riece-quit-server-process): Don't set timer if
riece-quit-timeout is nil.

* riece-options.el (riece-quit-timeout): Change custom type.
(riece-shrink-buffer-idle-time-delay): New user option.
(riece-max-buffer-size): New user option.

* riece-icon.el (riece-icon-add-image-region) [XEmacs]: Delete
extents if already exists.

* riece-emacs.el (riece-overlays-in): New alias.
(riece-delete-overlay): New alias.
(riece-kill-all-overlays): New function.
(riece-run-with-idle-timer): New alias.
(riece-cancel-timer): New alias.

* riece-display.el (riece-update-user-list-buffer): Kill all
overlays in buffer.
(riece-update-channel-list-buffer): Ditto.

* riece-commands.el (riece-command-set-operators): Reset group.
(riece-command-set-speakers): Ditto.