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

[Gene Czarcinski]

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