create new class to handle temp dir; deletion of temp dir works

Created by: joel-tuberosa

Instead of managing temp working directories from the outside of the yn00_pairwise function, temp dir are created and deleted after use within the function. The recursive_rm function was removed and the new context manager class TemporaryDirectory was inspired by the examples given by Nils von Barth in this post from stackoverflow: https://stackoverflow.com/questions/6884991/how-to-delete-dir-created-by-python-tempfile-mkdtemp.