* Update README.md

* Attempt to fix codecov: https://github.com/codecov/codecov-action

* Move --cov-report to setup.cfg

* Add is_dir_empty() and its tests

* Avoid using hard-coded tmp path

* Add remove_dir() and its tests

* Refine fileutils tests

* *args for all fileutils

* Adjust tests

* Prepare for v0.0.6

* fix style issue