Bug 11169: (follow-up) only count orders that have been placed

Bug 11169: (follow-up) only count orders that have been placed

This patch ensures that only orders that have been placed (i.e.,
orders whose basket is closed) are counted in the OPACAcquisitionsDetails
display.

To test:

[1] Turn on OPACAcquisitionsDetails and set AcqCreateItem to 'ordering'.
[2] Create an order for a record, but do not close the basket.
[3] View the record in the OPAC.  It should not display any order count.
[4] Close the bakset.
[5] View the record in the OPAC again.  This time, it should display
    the count of items on order.

Signed-off-by: Galen Charlton <gmc@esilibrary.com>
Signed-off-by: Chris Cormack <chris@bigballofwax.co.nz>
Signed-off-by: Tomas Cohen Arazi <tomascohen@gmail.com>