Bug 20322: (follow-up) Circulation page layout and design update

Bug 20322: (follow-up) Circulation page layout and design update

This follow-up makes some suggestions about how to push this further:

- Put content in four columns which reduces to two on smaller screens
- Adjust font size of large links
- Move Offline Circulation links into its own column
- Add image icons to the Firefox extension and Windows application
  download links
- Improve indentation in template

Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Mark Tompsett <mtompset@hotmail.com>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>