LP1995510 Bootstrap Opac: Inconsistent bevahior in the Bib Email Form

LP1995510 Bootstrap Opac: Inconsistent bevahior in the Bib Email Form

Fixes some of the inconsistencies and style issues with the Email form.

All of the drop-down lists will now refresh the page so that the preview
is updated.

The email field requires a value and must be in an email format.  The update
button is next to this field and is only enabled when there is a change in
 the field.

The subject field has been hidden with a 'Fixme' tag.  Currently the subject
is always 'Bibliographic Records' regardless of what is entered in the field.

The style has been changed to be more consistent with other pages in the opac.

Signed-off-by: Garry Collum <gcollum@gmail.com>