Add data about packaging

[brentzundel]

this PR adds a common schema for Instrument of Trade, which is a term of art for packaging material.

[nissimsan]

@brentzundel , "InstrumentOfTrade" seems like a re-invention of https://vocabulary.uncefact.org/LogisticsTransportEquipment . We already have this on Trace:
https://w3c-ccg.github.io/traceability-vocab/#TransportEquipment . I recommend using it instead, extending as needed.

[brentzundel]

@nissimsan Transport Equipment seemed to be shipping containers and trucks, rather than pallets and boxes. Are they really the same thing? If so I can extend transport equipment to include packing material and wood treatment stamps, but they seemed at different layers to me.

[nissimsan]

@brentzundel ,

You commonly distinguish returnable vs non-returnable.

Transport Equipment is returnable. This includes pallets:
https://vocabulary.uncefact.org/containedTransportEquipment
"A piece of transport equipment contained within this piece of logistics transport equipment, such as a pallet."

If you are looking for non-returnable, consider:
https://vocabulary.uncefact.org/Package

It doesn't seem like it should be necessary to invent a term here.

[TallTed]

@nissimsan — It seems worth noting that pallets are often not returnable (or at least, not returned), leading to endless ads for "FREE PALLETS!"

It seems that a loaded-and-wrapped pallet in a "shipping container" that gets loaded from dock to ship to railcar to semi-trailer could be interpreted as either a Package or a piece of containedTransportEquipment, by the linked definitions.

(I find it odd that they have contained Transport Equipment, but no uncontained Transport Equipment.)

All of which to say... UNCEFACT's ontology seems to be less than fully thought through, or at least, less than clearly documented. Confusion seems to be built in.