Bug 26289: Add missing variable definition to templates

Bug 26289: Add missing variable definition to templates

This patch puts definition of the missing "searchid" variable into an
include file to be used by various bibliographic detail pages. The
variable is required by several JavaScript functions.

To test, apply the patch and locate or create a record with no items.
Open the labeled MARC view and choose Edit -> Delete record. Confirm the
deletion. The deletion should complete correctly.

Perform the same test with the detail view, ISBD view,  MARC view, and
items view.

Signed-off-by: Amit Gupta <amit.gupta@informaticsglobal.com>
Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
(cherry picked from commit a4e922ffe8a5ea760f2401aca44b1dd9be97c7ec)

Signed-off-by: Lucas Gass <lucas@bywatersolutions.com>