Added ability to define answer option set at question level

[randywoods]

🗣 Description

Most maturity models use the same answer options for all of their questions. In the case of CMMC 2, there are 2 questions that deviate from that pattern and also present an Incomplete option. This modification allows the question-level answer set to be defined in MATURITY_EXTRA.

This branch also contains refinements to the CMMC 2 results scoring charts.

💭 Motivation and context

🧪 Testing

✅ Pre-approval checklist

• This PR has an informative and human-readable title.
• Changes are limited to a single goal - eschew scope creep!
• All future TODOs are captured in issues, which are referenced
  in code comments.
• All relevant type-of-change labels have been added.
• I have read the CONTRIBUTING document.
• These code changes follow cisagov code standards.
• All relevant repo and/or project documentation has been updated
  to reflect the changes in this PR.
• Tests have been added and/or modified to cover the changes in this PR.
• All new and existing tests pass.

✅ Pre-merge checklist

• Revert dependencies to default branches.
• Finalize version.

✅ Post-merge checklist

• Create a release.