Rename Subject Predicate Object to Thing Property Value

[joepio]

The RDF terminology subject predicate object is kind of unconventional in the computer world, and can confuse newcomers. It semantically makes sense, but since Atomic Data has subject-predicate uniqueness, it does not longer view these three rows as semantically relevant.

Perhaps we should call them something else.

• Subject Property Value
• Thing Property Value
• ID Property Value
• Key Property Value

I'm pretty sure about Property (since this should always be an Atomic Property) and Value, but I'm not sure about the subject replacement.

[joepio]

I've been using subject for everything. Still consider changing it, but let's close this issue for now.