Bug 9665: add RIS and BIBTEXT bibliographic record export to staff interface

Bug 9665: add RIS and BIBTEXT bibliographic record export to staff interface

The OPAC offers RIS and BIBTEX as choices for bibliographic downloads,
but the staff client was missing these options. This patch adds them.

To test, view a record in the staff client (detail.pl, MARCdetail.pl,
etc.) and click the "Save..." toolbar button. BIBTEX and RIS should be
available and functional.

Signed-off-by: David Cook <dcook@prosentient.com.au>
Signed-off-by: Chris Cormack <chrisc@catalyst.net.nz>
Signed-off-by: Galen Charlton <gmc@esilibrary.com>
(cherry picked from commit 4b9a6d803f7ad11a4e077140820bfeda0d4d196a)
Signed-off-by: Tomas Cohen Arazi <tomascohen@gmail.com>
Nice fix, works as expected.