Enhance summarize

Fix #111 (closed)
Wasn't sure what you wanted to do about return type hints though.

Also I wanted to make summarize more readable and commented. I had hard times every time I was back on it. I believe now it's far better Used the recursive trick for list, again, in stip_path() ! I took the liberty to shorten these new strip param names, since we did not release 2.0 yet it's still time ^^