Hello,

I would like to package python-markdownify for Gentoo Linux, however I encounter a problem: setuptools tries to install the top-level directory "tests". I am not a Python expert, but I think that it could be fixed by specifying the "exclude" parameter of find_packages(). It would restrict the installed package list.

In setup.py, packages=find_packages() could be rewritten as packages=find_packages(exclude=["tests"])).