Fixes a bug where sale orders with a partner_shipping_id not within the
same commercial entity as their partner_id could not have collect
carrier accounts set after being confirmed.
The issue stemmed from the fact that the sale order's recipient_id field
was being set to partner_id, while the created delivery order had
recipient_id set to its partner_id, which is the partner_shipping_id of
the sale order. In other words, the sale order recipient was incorrectly
set to the main partner instead of the shipping address.
This commit adds a test that was previously failing in this scenario. It
also properly sets the recipient_id on the transport selection wizard
and on sale orders themselves, fixing the issue.
When adding transport charges to a sale order via the "Add Shipping"
button, the line's description now contains the delivery billing mode
and account number when applicable.
Fixes#112
