Hyperlinks in notes

[dev-guy]

Is your feature request related to a problem? Please describe.
Support markdown hyperlink in notes

Describe the solution you'd like

[this is a link](https://example.com/foo)

Describe alternatives you've considered
I can type a URL but it's not a hyperlink

Additional context
Notes are awesome and address a use case that is missing from Mermaid, ie the fact that a diagram requires an explanation. More support for Markdown will make notes a killer feature.