Bug 7882: Add ability to move and reorder fields in MARC editor

Bug 7882: Add ability to move and reorder fields in MARC editor

Use jQueryUI sortable to make fields and subfields moveable in the
MARC editor for both records and authorities.

This patch convert items from div's to ul's and consequently alter css
and js to match. It also replace the up arrow with a more adapted icon
(from font awesome).

Primary authorship by Elliott Davis.

To Test:

1. Add or edit a record in cataloguing module.
2. You should be able to move the fields and subfields around.
    - You can click on any part of the element to drag it, the move
    icon to the left of the item is a good place to do it.
    => You can only change the order of fields of the same tag.
3. Make sure all of the javascript driven fonctionnality still work :
    - Duplicate fields/subfields
    - Remove fields/subfields
    - Using the tag editor for control fields or to link authorities
    - etc
4. Reorder some fields/subfields and save the record.
5. Edit the record again.
6. The order in the editor should match the changes which were saved.
    - Empty subfields should appear after the ones with content.
7. Repeat steps 1-6 with the authority editor.

Signed-off-by: Séverine QUEUNE <severine.queune@bulac.fr>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>