Bug 13700: Fix item search templates for translation

Bug 13700: Fix item search templates for translation

Since translator rebuild HTML tags with double quotes for attributes
values, use double quotes in english template too and escape them with
backslash.

Signed-off-by: Bernardo Gonzalez Kriegel <bgkriegel@gmail.com>
It works well!!

Test:
1) Intall translation  (de-DE, es-ES)
2) to Go to item search, in english, do a search that gives results
3) Switch language, repeat search, result's table does not render
4) Apply patch
5) Install translation again
6) Repeat 3, now results are displayed

No koha-qa errors

Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>
Signed-off-by: Tomas Cohen Arazi <tomascohen@gmail.com>