Running tests on all supproted Python versions

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

With a range of different Python versions supported, it might be

somewhat difficult to run the tests against all the posible versions

of Python depending on distribution used for development.

The projects comes with a `Vagrantfile <https://www.vagrantup.com/>`_

to make this easier. To run all tests within a Vagrant machine,

perform the following steps:

1. Go to project root directory::

     workon gimmecert

2. Bring up the Vagrant machine (this may take a while since it will

   build the necessary Python versions)::

     vagrant up

3. Log-in into the Vagrant machine::

     vagrant ssh

4. Change directory::

     cd /vagrant

5. Clean Python caches to ensure your main development machine files

   do not interfere::

     py3clean

6. Run tests against all available environments::

     tox