Enhance FedRAMP JSON schema and add auto-generated documentation

[dan-fedramp]

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Overview

This pull request introduces improvements to the FedRAMP.schema.json file by adding detailed descriptions to properties for clarity and enhancing the validation rules. Additionally, it implements json-schema-for-humans to automatically generate documentation for the schema. The README has been updated with instructions for generating this documentation.

Changes

• Added detailed descriptions to properties in FedRAMP.schema.json.
• Enhanced schema validation rules to improve usability.
• Implemented json-schema-for-humans to generate human-readable schema documentation.
• Updated README file with documentation generation instructions.

Checklist

• Tests added or updated, if applicable
• Documentation updated, if needed
• Validation rules tested and verified