feature request: support for headings to organize functions

[AlexAtCCRI]

firstly, this program is awesome. thank you.

this may be asking too much from pdoc3, but in my code i usually have comment sections which are like markdown headings to organize the functions. kind of like a module-level doc-string. is there anyway to implement this with pdoc? i dont want to explicitly write a list of functions like i have to do with sphinx, because thats annoying, and easy to forget some.

example use case is a simple project with little more than a __init__.py. but with many functions it is nice to have headings to organise them. thoughts?