This module allows to define min, max and multiple order quantity on product.
Min and Max order quantity is either required or recommanded.
If you check "Force mini/max Qty" on product the min/max qty do not block sale
order.
This can be used if the available stock is less then the min qty
or if you want to sell sample products.
Max qty can be used if we dont want to sale more than available qty
(end of series product)

Setings are defined on product, if values are not set we use settings from
product template.
If settings are not set on product template we use settings from
product category otherwise parent category.
