Bug 11752: display the correct frequency for serial subscriptions in OPAC details

This fixes bootstrap and prog by modifying the description displayed
in the OPAC's detail of serials.

RM NOTE: this patch does not cover the case where custom serial
frequencies have been defined.

TESTING to reproduce
- create/find a serial with a 1/week periodicity (4 in the database)
- Find it in the opac-detail.pl, click "more details" at the bottom
- validate the string.  Before the patch, it will say:
"The current subscription began on 2013-12-06 and is issued every 3
 weeks for 26 issues"

The "every 3 weeks" is clearly wrong.
In fact any periodicity chosen would display a wrong description, not
matching the staff interface.

After the patch, the display is corrected.

As a bonus, the "every 2 years" now has a description, where it had
none before.

Signed-off-by: Chris Cormack <chris@bigballofwax.co.nz>
Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>
Signed-off-by: Galen Charlton <gmc@esilibrary.com>
(cherry picked from commit 7f1e949ea0e8d05b641ddbcb4582a3e1bc913ecd)
Signed-off-by: Fridolin Somers <fridolin.somers@biblibre.com>
Bug 11416: fix case where serials item editor was incorrectly hiding fields

In serials/serials-edit.pl, if an item field is hidden from the OPAC,
it will not display in the editor, even if the field is marked as
visible in the staff intranet and editor. However, the field is still
displayed correctly in the items editor ( additem.pl ).:

Test Plan:
1) Select an item-level field ( e.g. non-public note )
2) Create a serial using the default framework ( or one of your choice )
3) For that framework, mark the chosen field as visible from the
intranet and editor, but not the opac.
4) Receive an item for this serial, note your field does not display
5) Use the biblio item editor to add an item ( additem.pl ), not the
field displayes
6) Apply this patch
7) Repeat step 4, not the field displayes

Signed-off-by: Kim Schwant <kim.schwant@courts.in.gov>
Signed-off-by: Jonathan Druart <jonathan.druart@biblibre.com>
PrepareItemrecordDisplay is only used for editor (-4 < hidden < 4)

Signed-off-by: Galen Charlton <gmc@esilibrary.com>
(cherry picked from commit f14020780836c5fbc65331b3918b843761481c36)
Signed-off-by: Fridolin Somers <fridolin.somers@biblibre.com>