Bug 26441: Move translatable strings out of catalog-strings.inc into catalog.js

Bug 26441: Move translatable strings out of catalog-strings.inc into catalog.js

This patch moves translatable strings out of catalog-strings.inc into
catalog.js, wrapped in the double-underscore function for
translation.

To test that each affected string correctly appears in the interface:

- View the details for a bibliographic record which has items attached.
- From the Edit menu, choose "Delete record." You should get an alert,
  "X item(s) are attached to this record. You must delete all items
   before deleting this record."
- From the Edit menu, choose "Delete all items." You should get an
  alert, "Are you sure you want to delete the X attached items?"

- When logged in as a user with acquisitions and cataloging privileges,
  view the details for a bibliographic record which is used in an order
  in Acquisitions. Delete any items attached.
- Choose "Delete record" from the Edit menu. You should get an alert,
  "Warning: This record is used in X order(s). Deleting it could cause
  serious issues on acquisition module. Are you sure you want to delete
  this record?"
- In Acquisitions, view a basket containing orders. Cancel the
  order for a title in the basket. Open the detail page for the title in
  the cancelled order. Try to delete it. You should get an confirmation,
  "X deleted order(s) are using this record. Are you sure you want to
  delete this record?"
  - Perform the same test as a user with cataloging but not acquisitions
    privileges. The alert should say "X deleted order(s) are using this
    record. You need order managing permissions to delete this record."

- When logged in as a user with cataloging but not acquisitions
  privileges, view the details for a bibliographic record which is used
  in an order in Acquisitions. Delete any items attached.
- Choose "Delete record" from the Edit menu. You should get an alert, "X
  order(s) are using this record. You need order managing permissions to
  delete this record."

- View the details for a bibliographic record which has a hold.
- Choose "Delete all items" from the Edit menu. You should get an alert,
  "X hold(s) on this record. You must delete all holds before deleting
  all items."
- View the details for a bibliographic record which has no items.
- Choose "Delete record" from the Edit menu. You should get an alert,
  "Are you sure you want to delete this record?"
- Choose "Edit items in a batch" from the Edit menu. You should get an
  alert, "This record has no items."

I could not find any instance of the PopupZ3950Confirmed function in
catalog.js being triggered so I don't think the associated string can be
tested.

TESTING TRANSLATABILITY

- Update a translation, e.g. fr-FR:

  > cd misc/translator
  > perl translate update fr-FR

- Open the corresponding .po file for JavaScript strings, e.g.
  misc/translator/po/fr-FR-messages-js.po
- Locate strings pulled from
  koha-tmpl/intranet-tmpl/prog/js/catalog.js for
  translation, e.g.:

  msgid "This record has no items."
  msgstr ""

- Edit the "msgstr" string however you want (it's just for
  testing).
- Install the updated translation:

  > perl translate install fr-FR

- Switch to your newly translated language in the staff client
  and repeat the test plan above. The translated strings should
  appear.

Signed-off-by: David Nind <david@davidnind.com>
Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>