Create authorities that only contain controlled subfields (LP 712496)

Create authorities that only contain controlled subfields (LP 712496)

Selecting "Create authority" on a field containing uncontrolled subfields
would generate an authority record that contained those uncontrolled
subfields. This would, in turn, prevent the "Validate" button from operating
correctly - if you added a 700 with $a and $c subfields, clicked "Create
authority", and then immediately clicked "Validate", the field would show
up as red.

Now we filter out the uncontrolled subfields before they get sent to
the "Create authority" function, avoiding this validation problem.

git-svn-id: svn://svn.open-ils.org/ILS/trunk@19404 dcc99617-32d9-48b4-a31d-7c20da2025e4