Bug 18467: Handle orders with deleted biblio when viewing a basket

Bug 18467: Handle orders with deleted biblio when viewing a basket

If the bibliographic record of an order has been removed, $order->{bibionumber}
is undefined. We need to handle this specific case correctly.

To test:
1 - Create a basket
2 - Order a bib
3 - Cancel order and delete record
4 - You cannot view basket
5 - Apply patch
6 - View basket
7 - There should not be an error
r calling count on undefined bib in basket.pl if order cancelled and
record deleted

Followed test plan, works as intended

Signed-off-by: Alex Buckley <alexbuckley@catalyst.net.nz>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>
Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>