As @complexpoint says I tried making a Markdown outliner and didn’t like the result in the end.
There is no formatting support in the latest 1.3.1 release. I am working on “inline” formatting in this current 1.4 preview release. Please try it out and let me know what you think.
Longer term (for headings and such) I will be adding options for row based formatting. That will be somewhere down the road, not in the 1.4 release that I’m now working on.