Bug 19028: Add 'shelving location' to holdings table in detail page

Bug 19028: Add 'shelving location' to holdings table in detail page

This patch adds the option to show shelving locations on a separate
column. This is controlled by a new syspref, 'OpacLocationOnDetail',
which replaces 'OpacLocationBranchToDisplayShelving', adding a
conveniente 'column' option.

The new 'Shelving location' column is conveniently added to the columns
configuration entry added by bug 16759 for this purpose.

The current behaviour is preserved.

To test:
- Apply this patches
- Run the upgrade:
  $ sudo koha-shell kohadev
 k$ cd kohaclone
 k$ perl installer/data/mysql/updatedatabase.pl
=> SUCCESS: Upgrade doesn't fail
- Have an item with shelving location set to something not void
- Have the item set home and holding libraries for testing purposes.
- Set 'OpacLocationBranchToDisplay' to 'home and holding libraries' [*]
- Visit the OPAC detail page for the record containing the item
=> SUCCESS: Both home and holding libraries are displayed.
- Loop through all OpacLocationOnDetail options (except from 'column', we leave it for later).
=> SUCCESS: Works as expected.
- Go to Administration > Columns settings
- Make item_shelving_location available in the OPAC section
- Reload the OPAC detail page
=> SUCCESS: No change
- Set OpacLocationOnDetail to 'on a separate column'
- Reload the OPAC detail page
=> SUCCESS: Shelving location is displayed on a separate column
- Sign off :-D

Sponsored-by: Dover
[*] For testing purposes

Signed-off-by: Owen Leonard <oleonard@myacpl.org>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>