Bug 20212: Make all biblioitems.* fields searchable

Bug 20212: Make all biblioitems.* fields searchable

Prior to this bug, only a few bilbio fields were actually searchable through
the orders API. This patch adds all of them to the mapping, so other
pages can take advantage of them.

My first approach was to add things as needed. But this is trivial to
make complete.

Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
Signed-off-by: Andrew Fuerste-Henry <andrew@bywatersolutions.com>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>