Add optional prop to metadata section

[david-waltermire]

Committer Notes

Added prop to the top-level metadata. This may be a possible solution to issue #397.

Also fixed a few small editorial issues in documentation.

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[wendellpiez]

Cool. thanks @david-waltermire-nist

So I just want it on the record I'm not actually entirely comfortable with the 'oscalization' of Metaschema e.g. the entire notion of props in this context. I'm willing to try it out, but I wonder if for v2.0 we can revisit. By that point maybe some of the props could become first-class elements?

Props are definitely good for playing with. 🎺

[wendellpiez]

Editorially, I think the common noun is "metaschema" for a single instance of Metaschema, alternatively "Metaschema module". Keeping in mind that module (as per the docs) means the composite not the bare unprocessed file before importing, that is the logical 'thing' that becomes a catalog model, and none of the files that compose that thing. The proper noun, "Metaschema", refers to a technology, not an instance.

I suggest the same for Metapath - "Metapath" is a technology, whereas "Metapath expression" or "Metapath path" (for those that are paths) or "metapath" (albeit confusingly) all refer to instances (strings that conform to the Metapath grammar).

What do you think? (Not a blocking request assuming we can also rectify later.)