Bug 23464: Update the process of quick spine label printing

Bug 23464: Update the process of quick spine label printing

This patch makes changes to the way quick spine label printing works,
either from the bibliographic details page or the Quick spine label
creator page.

To test, apply the patch and go to Tools -> Quick spine label creator.

 - Type or scan a barcode. Submitting the form should trigger a popup
   window with the spine label print page. The "print" button should
   be centered at the bottom of the window in a footer-like container.
   - If you have SpineLabelAutoPrint enabled, the print dialog should
     appear automatically.
   - After printing, the pop-up window should close and and focus should
     be returned to the barcode field.

Enable the SpineLabelShowPrintOnBibDetails system preference. View the
bibliographic details page for a record in the catalog.

 - In the holdings table, a "Spine label" column should appear as the
   second-to-last column. The column should contain "Print label"
   Bootstrap-style buttons.
 - Clicking a "Print label" button should trigger a pop-up window with
   the spine label print page. The behavior of the window should be the
   same as above.

Signed-off-by: Maryse Simard <maryse.simard@inlibro.com>
Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>