Bug 20948: Only display item-level hold info if first hold

Bug 20948: Only display item-level hold info if first hold

On the item list of the catalogue detail page we display next item-level
hold info even if it is not the next hold. That leads to confusion as it
will not necessarily be the accurate info.

This patch makes the following changes:
- Display the item-level hold only if it is the next hold (priority ==
1)
- Display "There is an item level hold on this item (priority=X)"
if there is at least 1 item-level hold placed on this item

Test plan:
- Place several next available holds on a single item record
- Place an item level hold on the item
- Go the the biblio detail page
=> Without this patch, the item will show the item level hold
=> With the patch you see "There is an item level hold on this item"
- Check the item in, confirm the hold
=> No changes, the item will show the waiting hold info
- Cancel all the holds except the item-level one
=> No changes, the item will how the item-level one

Signed-off-by: Lisette Scheer <lisetteslatah@gmail.com>
Signed-off-by: Marcel de Rooy <m.de.rooy@rijksmuseum.nl>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>