Bug 25728: Create AV when cataloguing a bibliographic record

Bug 25728: Create AV when cataloguing a bibliographic record

This whole patch set adds the ability to create a new authorised value
directly from the cataloguing module.
It will prevent the cataloger to leave and reload the page if they need
a new one.

Test plan:
If you are logged in with a patron with the manage_authorised_values
subpermission you will be able to:
* Edit a bibliographic record
* Search for a subfield linked to an authorised values (not the "fake"
AV like itemtypes, branches, cn)
* Click the dropdown list and start searching for a value that does not
exist
* Click enter
* Fill the fields in the popup
* Save
=> Your dropdown list has the new AV :)

Note: This does not work for the advanced editor. It does not have
select2 applied to the selects. I have hardly tried but failed.

Sponsored-by: Orex Digital
Signed-off-by: Hugo Agud <hagud@orex.es>
Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>