Simplify the Variables Files

[Project-42]

There should be not need to set so many different variables. Macs can be ramdomize with Random Mac Address Filter (https://docs.ansible.com/ansible/latest/user_guide/playbooks_filters.html#random-mac-address-filter) DHCP range should be obteine from the guests lists

[Project-42]

For now, added "localhost" as default KVM_HOST since I assume the playbooks will be executed locally from the kvm_host.
For that, lxml needs to be available and needed to be installed with "yum" intead of pip (I guess need to be related with user environment)