Update getting started docs

[KastanDay]

Description

Edit: PR is ready for review & merge.

See PR #298, this is a continuation of that work.

Review Time Estimate

• [ ] Immediately
• [ ] Within one week
• [x] When possible

Types of changes

• [ ] Bug fix (non-breaking change which fixes an issue)
• [ ] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• [ ] My change requires a change to the documentation.
• [ ] I have updated the CHANGELOG.md.
• [ ] I have signed the CLA
• [ ] I have updated the documentation accordingly.
• [ ] I have read the CONTRIBUTING document.
• [ ] I have added tests to cover my changes.
• [ ] All new and existing tests passed.

[robkooper]

This was originally slated to be merged into 1.19.3, however some issues were found and could not be merged. Deleting the release branch resulted in the original PR to be automatically closed.

[KastanDay]

The documentation is much improved and ready for final review by @lmarini or @robkooper