Bug 23148: Replace Bridge icons with transparent PNG files

Bug 23148: Replace Bridge icons with transparent PNG files

This patch adds SVG versions of the Bridge item type icon set to
misc/interface_customization/itemtypeimg/bridge. It adds some
new icons, and updates some existing icons. All GIF versions of the
icons are replaced with transparent PNG files.

Icon changes:

- English text has been removed from all icons
- New icon for "Periodical," to differentiate from "Journal"
- New icon, "Controller" for video games
- New icon for "Laserdisk" to differentiate from "DVD"
- New icon for "Kit" to differentiate from "Archive"
- New icon, "Reference books."
- Updated "badges" on "Juvenile book" and "Reserve book" to try to
  express the information without English-specific letters.

Before applying the patch, update some item types or collection codes
with Bridge icons. Apply the patch and run the database update process.

 - Open the advanced search page in the staff client and confirm that
   your item type or collection code icons were updated correctly.
 - Go to Administration -> Item types and edit an item type.
   - Check the "bridge" tab and confirm that the icon options look
     correct.

Signed-off-by: David Nind <david@davidnind.com>
Signed-off-by: Julian Maurice <julian.maurice@biblibre.com>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>