refactor Document.json

[zopalmer14]

Summary

Should resolve: #75

Relevant Documentation: Document

Changes to Document.json

• created accessURL property to create a way to link to the Document
• added accessURL to 'required' array
• mediaType - changed cardinality from 0..n to 0..1 (i.e., no longer an array) in line with James's recommendation
• removed $id field from all properties/subschemas - related to DCAT-US3 JSON Schema doesn't comply with standard #73
• changed order of properties to match documentation and to make it easier to remember which I'd reviewed (sorry if this ruined the diff)
• added individual author property from documentation; key/name: creator
• corporate author - adjusted key/name to corporateCreator
• publisher(s) as a literal - changed from a string to an array of strings; matches documentation and makes sense
• document type - adjusted key/name to type and title to "document type"; both originally category
• conformsTo - adjusted title to "conforms to"; matches documentation

Discussion Topics

• mediaType - could a single Document have multiple mediaTypes? What if a piece of documentation can be accessed as a .docx, .pdf, or .html file?
• Do we need multiple options for listing the publisher(s)/author(s)
• Should individual author and corporate author be an array rather than a single entry? If we did this, we could potentially consolidate the duplicative properties into one.
• identifier - should it be changed from an array of strings to a string (e.g., from 0..n to 0..1)? We changed this for Dataset but it has the otherIdentifier property and Document does not.

Documentation and jsonschema Desynchronization

I don't think these are particularly important to fix, and I also know we've discussed ditching the HTML documentation and generating the documentation from the jsonschema, but I thought I would list what I noticed here anyways:

• Documentation is generally missing the property descriptions/usage notes
• title - cardinality is 1..n in documentation, jsonschema is 1; does the language map change the cardinality?
• publisher - title is "publisher", but documentation says "publisher organization"
• identifier - cardinality is 0..1 in documentation, jsonschema is 0..n
• publication date (i.e., issued) - cardinality is 0..1 in jsonschema and class description, but is 0..n in property description
• abstract - cardinality is 0..n in documentation, jsonschema is 0..1; does the language map change the cardinality?
• description - cardinality is 0..n in documentation, jsonschema is 0..1; does the language map change the cardinality?