Update 800-53 JSON examples

[anweiss]

Committer Notes

To address #197, this includes updated JSON examples based on the latest data models in master and that which are equivalent to the 800-53 XML examples in the examples/SP800-53 directory.

Updates to oscalkit to reflect the latest data model are being tracked at docker-archive/oscalkit#1.

All Submissions:

• Have you followed the guidelines in our Contributing document?
• Have you checked to ensure there aren't other open Pull Requests for the same update/change?
• Have you squashed any non-relevant commits and commit messages? [instructions]

Changes to Core Features:

• Have you added an explanation of what your changes do and why you'd like us to include them?
• Have you written new tests for your core changes, as applicable?
• Have you included examples of how to use your new feature(s)?

[anweiss]

This PR is dependent on #143 so equivalent JSON examples can be generated.

[anweiss]

800-53 catalog, declarations and profile examples have been pushed. Waiting for FedRAMP profile cleanup to re-generate JSON equivalents.

[JJediny]

@anweiss this LGTM, is it worth breaking out the FEDRAMP update as another PR when ready and merge this first?

[anweiss]

@JJediny yea good idea. Will commit FedRAMP examples in another PR

[david-waltermire]

Regarding #197, this PR contains updated 800-53 examples. Another PR will be submitted for the FedRAMP examples once #185 is resolved. We need to validate the JSON content against the latest Metaschema generated JSON Schema, before accepting this PR. Also need to validate the XML content.

[iMichaela]

The examples appear accurate