Fixed bugs 1232, 1233 and 1234

Detailed changes:
> 2003-12-11  David Byers  <byers@lysator.liu.se>
>
> 	Fix bug 1233:
> 	* commands1.el (kom-change-priority): Pass old mship-type to
> 	lyskom-add-member-answer.
>
> 	Fix bug 1234:
> 	* lyskom-rest.el (lyskom-update-prompt): New prompts for when
> 	prioritised texts are in the letterbox, or the prioritised
> 	conference is the letterbox.
>
> 	Fix bug 1233:
> 	* commands1.el (lyskom-list-clients-collect): Deal with version
> 	set to nil.
>