Bug 15222: Add to cart option/other list options missing from OPAC lists display

Bug 15222: Add to cart option/other list options missing from OPAC lists display

This patch adds the option to add titles to the cart or a list from the
view of a list's contents.

To test you should have at least one public list with titles added.
Apply the patch and go to the OPAC.

- View a public list.
- In the toolbar at the top of the table of titles you should see "Add
  to cart" and "Add to list." The controls should be disabled.
- Check checkboxes for one or more titles on the list.
- The controls should now be enabled.
- Clicking the "Add to cart" button should add the selected titles to
  the cart.
- If you are not logged into the OPAC, clicking the "Add to list" button
  should trigger an alert, "You must be logged in..."
- Log in to the OPAC and view the list again.
- Confirm that the "Add to list" control should trigger a popup allowing
  you to add your selected titles to an existing or a new list.

Signed-off-by: David Nind <david@davidnind.com>
Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>