Decision tree

[SGOmS]

Hello, I think a decision tree would fit in really well into mermaid.

Im thinking of something like the operator decision tree on rxjs.dev

Existing syntax for tree structures could be reused.

There should be:

• Possible to see previously selected options
• "Back" button
• "Back to start" button
• the possibility for treeleafs to use a Link (href or something) when clicked on

Please let me know what you think. I thought it would be useful to help less experienced colleagues find stuff faster in our documentation