* Create python3and2
Adding tests to see if dnf still works when python-2 and python-3 are installed.
* Update main.yml
Include the tests that run on python 2 and python 3, based on the package manager.
* Update dnf.py
Use python3-dnf by default, otherwise python2-dnf.
* Rename python3and2 to python3and2.yml
Rename.