Bug 16415 - Layout problem on staff client detail page if local cover images are...

Bug 16415 - Layout problem on staff client detail page if local cover images are enabled

This patch fixes a layout problem which appears on the staff client
bibliographic detail page if local covers are enabled but Amazon covers
are not.

To test, apply the patch and turn off AmazonCoverImages.

- Enable the LocalCoverImages system preference and locate or create a
  record which has a local cover image associated with it.
- View the bibliographic detail page. The bibliographic details should
  display in two columns, with text on the left and local cover image on
  the right.
- Test with AmazonCoverImages and LocalCoverImages enabled.
- Test with AmazonCoverImages enabled and LocalCoverImages disabled.

All combinations are OK.
Signed-off-by: Marc Véron <veron@veron.ch>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
Signed-off-by: Brendan Gallagher <bredan@bywatersolutions.com>