Markdown in Dataflows

My idea is to allow for a markdown file in a dataflow.

Use Case: Adding a README file with more detailed documentation than commenting. This would improve documentation where the work is done and help teams with development and troubleshooting. When someone passes off their work, I could read the README and be off and running.

Bonus: Being able to import and add additional notes and information from the query dependencies diagram using Mermaid.