Bug 18177: remove aqbooksellers.othersupplier

Bug 18177: remove aqbooksellers.othersupplier

This patchset removes some columns from the aqbooksellers table that are
not used:
 * booksellerfax
 * booksellerurl
 * bookselleremail
 * othersupplier
 * currency

The first 3 ones are certainly leftover from bug 10402.

Test plan:
For each for these fields you will make sure that they cannot be edited
from the interface.

Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
Signed-off-by: Marcel de Rooy <m.de.rooy@rijksmuseum.nl>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>