Bug 18660: Translatability: Get rid of template directives [%% in translation for...

Bug 18660: Translatability: Get rid of template directives [%% in translation for patroncards-errors.inc

Translation for koha-tmpl/intranet-tmpl/prog/en/includes/patroncards-errors.inc
contains a lot of (partial) template directives like:
%%]%s %sLayout: [%%

This patch fixes it

To test:
- Verify that code changes make sense
- Apply patch
- Create a translation (cd misc/translator , then: perl translate create aa-AA
- Verify that in po/aa-AA-staff-prog.po contains no fragments like %%] or [%%
  for patroncards-errors.inc
- Try to get an error: Try a link like
  http://[YOUR SERVER]/cgi-bin/koha/patroncards/create-pdf.pl?batch_id=1&template_id=999&layout_id=999&start_card=1
  ...where template_id and layout_id do not exist

(Amended for comment #2 2017-06-05 mv)
(Amended for comment #6 2017-08-02 mv)

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