Update this formula to the new standards

[baby-gnu]

Hello.

I started to make this formula compliant with what is done in template-formula.

Here is the list of planned tasks:

• Add kitchen tests (Feature/add kitchen tests #35)
• Add semantic release
• Manage the python2 / python3 problem for libvirt-python
• Enforce CI check to be able to merge a pull request
• Update unsupported OSes
• Divide the formula in several components (server, client) to address unable to install only clients package without daemon and qemu stuff #27
• Switch to TOFS
• Running the formula without specific pillar should provide the OS default configuration

[baby-gnu]

I'm starting with the kitchen tests, they will not pass until the formula is reworked to support python2/python3 packages and the other OS used by the kitchen matrix.