Bug 31338: (follow-up) add special class and add also to OPAC

Bug 31338: (follow-up) add special class and add also to OPAC

In order to easily hide this new text, this patch adds the class "included-see-from-headings-info".

Also uses <div> instead of <p>.

And adds the same feature to OPAC.

Signed-off-by: Barbara Johnson <barbara.johnson@bedfordtx.gov>
Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>
(cherry picked from commit 6acdfd0493a472232cc265d7b1cac8abcff94add)
Signed-off-by: Jacob O'Mara <jacob.omara@ptfs-europe.com>