Bug 11769 - Use validation plugin when creating new MARC framework

Bug 11769 - Use validation plugin when creating new MARC framework

The page for adding a new MARC framework includes some custom form
validation JavaScript which can be removed in favor of HTML5 validation
attributes and Koha's built-in validation plugin. This patch does so.

To test, apply the patch and go to Administration -> MARC bibliographic
framework -> New framework. Try submitting the form without entering a
tag number. This should trigger a validation warning.

Submission of the form with valid data should work correctly. Editing an
existing framework should also work correctly.

Patch behaves as expected.
Signed-off-by: Marc Véron <veron@veron.ch>
Signed-off-by: Katrin Fischer <Katrin.Fischer.83@web.de>
Signed-off-by: Galen Charlton <gmc@esilibrary.com>