Bug 5984 : Allowing the librarians to hide items in the Opac using a system preference

Bug 5984 : Allowing the librarians to hide items in the Opac using a system preference

Squashed commit of the following:

commit 72b578928b287ba3b5fa8965e42ff1ccbdf9013a
Author: Matthias Meusburger <matthias.meusburger@biblibre.com>
Date:   Wed Oct 20 11:26:46 2010 +0200

    Bug 5984 : MT4587, Follow-up: Hiding rules are now in a syspref

commit d95329955f976900afdafa82fe0a1699e8e892dc
Author: Matthias Meusburger <matthias.meusburger@biblibre.com>
Date:   Tue Oct 19 15:19:16 2010 +0200

    Bug 5984 : MT4587, Follow-up: Adds yaml config file for custom opac items hiding

commit 6777c1a97700b77095e4e499ca73040bf94271e2
Author: Matthias Meusburger <matthias.meusburger@biblibre.com>
Date:   Mon Oct 18 11:14:03 2010 +0200

    Bug 5984 : MT4587 : Adds yaml config file for custom opac items hiding

Signed-off-by: Claire Hernandez <claire.hernandez@biblibre.com>
Signed-off-by: Chris Cormack <chrisc@catalyst.net.nz>