Bug 36099: count and holdcount template vars into JS vars should default to 0 if...

Bug 36099: count and holdcount template vars into JS vars should default to 0 if empty

Visit:
http://localhost:8081/cgi-bin/koha/catalogue/detail.pl?biblionumber=4321
Notice you have 2 console errors:
1) Uncaught SyntaxError: Unexpected token ';'
2) Uncaught ReferenceError: biblionumber is not defined

Apply patch. Repeat. Notice no error shows.
Visit an existing biblionumber. Confirm all is well.

Signed-off-by: Owen Leonard <oleonard@myacpl.org>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
Signed-off-by: Katrin Fischer <katrin.fischer@bsz-bw.de>
(cherry picked from commit f94d763b6a5d671c4860db76263f72d0643b7555)
Signed-off-by: Fridolin Somers <fridolin.somers@biblibre.com>