add UUID options

[raspbeguy]

I noticed that the only way to makes changes to an exiting VM (e.g. adding some memory, adding a NIC, etc...) is to re-define the VM with an XML containing the UUID. So I added the possibility to manually give an UUID or let Ansible generate one by hashing the VM name.

• libvirt_vm_default_uuid_deterministic is the default setting for all the VMs. Default to false not to break existing setups.
• For each VM, you can manually setup an UUID with uuid property.
• For each VM, you can override libvirt_vm_default_uuid_deterministic with uuid_deterministic property.

[markgoddard]

Nice idea

[markgoddard]

Thanks