Bug 16516: Define the showListsUpdate JS function at the OPAC

Bug 16516: Define the showListsUpdate JS function at the OPAC

Bug 12233 removes the declaration of the showListsUpdate JS function for
the OPAC.
It results in a JS error (ReferenceError: showListsUpdate is not
defined) when a user tries to add selected titles to a list if no title
is selected.

Test plan:
Launch a catalogue search
Select a list in the "Select titles to" dropdown list
=> Without this patch you will get the JS error
=> With this patch you will get a JS alert "No item was selected"

Signed-off-by: Owen Leonard <oleonard@myacpl.org>
Signed-off-by: Marcel de Rooy <m.de.rooy@rijksmuseum.nl>
Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>