Bug 8600: can now remove search input fields in OPAC advanced search form

Bug 8600: can now remove search input fields in OPAC advanced search form

If you follow the 'More options' link in the OPAC
advanced search form, each search input field after
the first now has a '-' button that lets you remove
the box.  This complements the '+' buttons that
already existed that allow the user to add additional
input fields.

Signed-off-by: Cedric Vita <cedric.vita@dracenie.com>
Signed-off-by: Chris Cormack <chris@bigballofwax.co.nz>
Signed-off-by: Galen Charlton <gmc@esilibrary.com>
(cherry picked from commit 0d6bd380ba644ce2cf36a40edbfa5e231e1e19ab)
Signed-off-by: Tomas Cohen Arazi <tomascohen@gmail.com>