Don't reveal errors to public, and improve messages to internal.
- Previously errors about list-config etc. would have been included in bounces. Now only the admins get to know the details, bounces only tell about a fatal error. Except ListNotFound, that error is still put into the bounce.
- Include listdir in message of ListPropertyMissing-error. Before there was no way to tell which list this was referring to.
Edited by paz