Gyuricska Milán / cloud

commands: init command extended with default node, users, groups, permissions and detects kvm hardware acceleration presence.

* adds default node
* adds test groups: 'Administrators', 'Powerusers', 'Users'
* adds test users: 'admin', 'poweruser', 'user'
* adds KVM present notification for Administrator
* shares 'vm' network with groups

Changes:
* Use argparse instead of optparse: https://docs.djangoproject.com/en/1.11/releases/1.10/#features-removed-in-1-10
* convert print to self.stdout.write(), Django documents suggest it: https://docs.djangoproject.com/en/1.11/howto/custom-management-commands/#module-django.core.management