Bug 15773: Fix and standardise checkboxes code in framework

Bug 15773: Fix and standardise checkboxes code in framework

When creating a new subfield for an authority framework, the checkboxes
don't behave as they should.
If you click on the 'repeatable', 'mandatory' or 'is url' checkbox's
label, the checkbox from the second tab will be checked/unchecked.
This is caused by a non-unique id of the input element.

I have found this bug when working on the removal of CGI::checkbox in
both admin/auth_subfields_structure.pl and
admin/marc_subfields_structure.pl scripts.

This patch remove the use of CGI::checkbox as well as the generation of
html code from these 2 pl scripts (which should be avoided).
The code these scripts are now pretty similar.

Test plan:
Add/modify/remove subfield for a MARC framework and an Authority
framework.
Use as many field as possible and confirm that the values are correctly
inserted/displayed.

Signed-off-by: Hector Castro <hector.hecaxmmx@gmail.com>
Works as advertised

Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Brendan Gallagher brendan@bywatersolutions.com