Add sold quantity to product loan history

In stock-> product history, the loan history only showed the loan
quantity and the returned quantity, not the sold quantity.
Added the column sale_quantity to the productstockdetails.py
in order to show the sold quantity.

Change-Id: I477635ba822ecce545f47a6c912ecd4e4b23e182
Fixes: http://bugs.async.com.br/show_bug.cgi?id=5473