Bug 20220: Move template JavaScript to the footer: Holds

Bug 20220: Move template JavaScript to the footer: Holds

This patch modifies the holds template so that JavaScript is included in
the footer.

To test, apply the patch and initiate the process of placing a hold.
Throughout the process JavaScript-based interactions should work: Patron
autocomplete, datepickers, DataTables, cancel confirmations, etc.

Signed-off-by: Claire Gravely <claire.gravely@bsz-bw.de>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>