Bug 25320: Move translatable strings out of merge-record-strings.inc into merge-record.js

Bug 25320: Move translatable strings out of merge-record-strings.inc into merge-record.js

This patch eliminates the use of a separate include file containing
translatable strings in favor of embedding translatable strings in the
JavaScript itself.

To test, apply the patch and clear your browser cache if necessary.

 - Perform a catalog search in the staff interface.
 - Select two results to merge. Click Edit -> Merge records.
 - Click "Next" on the "Merging records" page.
 - On the "Source records" page click the second tab where all the
   checkboxes are unchecked.
   - Check the box for a tag which is non-repeatable, e.g. 245.
     - You should see a message, "The field is non-repeatable and
       already exists in the destination record. Therefore, you cannot add it."
   - Check the box for a subfield which is non-repeatable, e.g. 245$a.
     - You should see a message, "The subfield is non-repeatable and
       already exists in the destination record. Therefore, you cannot
       add it."

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 prog/js/merge-record.js for
   translation, e.g.:

   #: koha-tmpl/intranet-tmpl/prog/js/merge-record.js:72
   msgctxt "Bibliographic record"
   msgid ""
   "The field is non-repeatable and already exists in the destination
   record. "
   "Therefore, you cannot add it."
   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 string 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>