[libvirt] [PATCH 0/2] updated/working patches for netcf backend and virsh commands for virInterface*

These are updated versions of patches I previously sent: 1 - add iface-* commands to virsh to expose virInterface* functions to the cli. 2 - add the netcf backend driver. These haven't been exhaustively tested, but appear to work in simple smoke tests. Note that they all depend on the submitted-but-not-yet-committed virConnectListDefinedInterfaces() patch.