Adds the ability to save individual authority records in MADS, MARCXML, or
binary MARC format to the staff client.
To test:
1. Apply patch
2. View authority record in staff client
3. Try saving record as MADS, MARCXML, and MARC, and confirm that the
resulting files are what you expect
Signed-off-by: Katrin Fischer <Katrin.Fischer.83@web.de>
Works nicely, tested different export options on different records.