[libvirt] [patch 0/4] checkpoint functionality

OK. Another run at producing a function that helps the likes of me backup my kvm Windows servers. 'virsh checkpoint domain file [script]' is what the following patch set (against cvs) enables. Modelled on the virDomainSave function it takes an optional script which it will execute (and pass the name of the domain as an argument) while the domain is paused, then resume the domain. By the by stability is coming along nicely since 0.6.0. Thanks! Matt McCowan