[EPIC] Write OSCAL content creation tutorials

[david-waltermire]

User Story:

As an OSCAL content creator, I need to understand how to create OSCAL content by hand. This will help me create content until suitable content creation tools exist for me to use.

Goals:

Create a series of tutorials covering content creation topics.

Each tutorial will need to provide:

• An explanation of what prerequisite knowledge the reader must have.
• Information about any tools needed for the tutorial, including how to download, install, and use the tool.
• A brief discussion of the OSCAL concepts, including pointers to the OSCAL documentation pages for more information.
• A step-by-step walkthrough explaining how to create the different parts of the OSCAL content. Each step should include examples in XML, JSON, and YAML.
• A full completed example at the end of the tutorial in XML, JSON, and YAML.

Initial tutorials will include:

• Creating a basic OSCAL catalog (Develop Tutorial #1: Creating a simple OSCAL control catalog #592)
• Creating a basic OSCAL profile (Develop Tutorial #2: Creating a simple OSCAL profile #593)
• Creating a basic OSCAL system security plan (Develop Tutorials Set #3: Creating a set of simple tutorials describing how to generate an OSCAL SSP. #594)

Other tutorials may address #567, #572.

Dependencies:

• A simple tool is needed to provide for validation capabilities. (Update the CLI tool to support the latest OSCAL models oscal-tools#3)

Acceptance Criteria

• All OSCAL website and readme documentation affected by the changes in this issue have been updated. Changes to the OSCAL website can be made in the docs/content directory of your branch.
• A Pull Request (PR) is submitted that fully addresses the goals of this User Story. This issue is referenced in the PR.
• The CI-CD build process runs without any reported errors on the PR. This can be confirmed by reviewing that all checks have passed in the PR.

[david-waltermire]

Issue #293 previously identified this work. Closing the old one in favor of this issue.