* riece-filter.el (riece-sentinel): Simplified.

* riece-filter.el (riece-sentinel): Simplified.

* riece-display.el (riece-user-list-update-buffer): Check the
existence of riece-user-list-buffer.
(riece-channel-list-update-buffer): Check the existence of
riece-channel-list-buffer.
(riece-set-window-points): Ditto.

* riece-commands.el (riece-command-open-server): Simplified.
(riece-command-toggle-channel-buffer-mode): Set
riece-save-variables-are-dirty to t.
(riece-command-toggle-user-list-buffer-mode): Ditto.
(riece-command-toggle-channel-list-buffer-mode): Ditto.

* riece-server.el (riece-start-server): Abolish.
(riece-open-server): Set riece-server-process-alist and
riece-server-process here.