changing the way subjects are build in detail.pl

changing the way subjects are build in detail.pl

If you have a $9 as authority, then you can directly search on an=<koha-auth-number>

For example, if you have :
600$912045$aEurope$xFrance$xMarseille (Europe--France--Marseille as subject of the biblio)

The link must be "an=12045"

The link is not changed in case there is no $9 (still apply on each term, one by one)

Signed-off-by: Chris Cormack <crc@liblime.com>
Signed-off-by: Joshua Ferraro <jmf@liblime.com>