Bug 23319: Implement blocking errors for neworderbiblio and basket.pl

Bug 23319: Implement blocking errors for neworderbiblio and basket.pl

To test:
1 - Hit neworderbiblio with a query and no vendor
    http://localhost:8081/cgi-bin/koha/acqui/neworderbiblio.pl?q=cat
    Or, add to basket from existing record with a search
    Refresh the page (url has no parameters)
2 - Get an internal server error
3 - Add bookseller
    http://localhost:8081/cgi-bin/koha/acqui/neworderbiblio.pl?q=cat&booksellerid=1
4 - Click 'Order' on a result
5 - Internal server error
6 - Apply patch
7 - Repeat 1-4, you get 'Vendor not found' or 'Basket not found'

Signed-off-by: Maryse Simard <maryse.simard@inlibro.com>
Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>