Configuration option to use `*` or `+` Markdown lists

According to original markdown specification:

lists can use * or + or - .

(btw. considering that * is suggested first, it IMHO should be considered default).

Therefore, I would love to have option to configure which is used in given graph, i.e. * or + or -.

(As a bonus, which is used for which level of indentation!)

Ideally after configuration , generated markdown files could e.g. use * :

* A
    * foo
* B
    * bar
* C