Bug 17852; Multiple URLs (856) in list email are broken.

Bug 17852; Multiple URLs (856) in list email are broken.

Test Plan
1: Add multiple urls to a biblographic record
2: Add the biblographic record to a list and then email it.
3: See that the links are broken and have been merged into one.
4: Apply patch
5: Send the list again and see that the links work

Signed-off-by: Owen Leonard <oleonard@myacpl.org>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
Signed-off-by: Mason James <mtj@kohaaloha.com>
(cherry picked from commit bcbd75fba2bc69b3aa26672db16d350a09d48c25)
Signed-off-by: Julian Maurice <julian.maurice@biblibre.com>