2015239577 - Added supplier price list import setting

Added the setting “Use delivery text from supplier for products with empty or zero availability” in the supplier price list import section. Works like this: - if the field with information about the availability of goods from the supplier is filled in the price list, then the value from this price list field will be taken into the availability text, as before; - if the field with the availability text in the price list is not filled in, then the value of the “delivery text” field from the supplier’s card will be added to the availability text