[libvirt] Proposal: no dnsmasq (no dhcp and no dns) and no radvd option

Laine mentioned something yesterday that got me to thinking: being able to specify that dnsmasq is not to be started for an interface. Let me expand that by saying that libvirt would not start dnsmasq for either dns or dhcp and also would not start radvd. However, the IPv4 and IPv6 gateway addresses would be defined on the virtual network interface and the "usual" iptables and ip6tables rules would be in force. This would allow a user to configure dnsmasq to meet any user desires or use something completely different instead of dnsmasq. Questions: Useful? Worth the time and effort? And then there is how should this be specified in the network xml file? ... some new parameter? ... A subperameter of <dns> such as <dns disable='yes' /> ? ... a subparameter of <bridge> such as <bridge name="virbr0" dns="disable" /> ? Comments? Suggestions? Gene