Previously DNS servers could be set for interface but they were used only
when interface address was set to static. This change allow to set (or
remove) DNS servers for interfaces regardles of IP address method.
Using AH based authentication generates duplicate announces from master:
IPSEC-AH : sequence number 34831 already processed. Packet dropped.
Use insecure (unencrypted) authentication for announcement pakets until
this is sorted out.
Combine interfaces and network_ether_interfaces into one common
variable network_interfaces. Provisioning uses format:
network_interfaces:
- device: device name eg. vio0 or eth0
vlan: vlan id for this interface
mac: mac address for interface (optional)
Additionally network role will use more settings to configure
interface.
