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* Add initial stab at generic ASCII data parsing, for employee file.
* Add ``AdjectivePrice`` model, ``Item.adjective_price`` relationship.
* Add some convenience properties to ``ElectronicCoupon`` model.
* Add ``ITEM_TYPE`` enumeration, and ``Item.item_type`` convenience property.
* Add "failsafe" for model integer properties, with logged warning.
* Refactor ``db`` sub-package a bit.