New implementation of network interfaces

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.

playbooks/include/vm-create.yml

@@ -24,11 +24,13 @@
       {% endif %}
 
     virt_install_network: >-
-      {% for item in interfaces %}
-      {%   if item[1] is defined %}
-      --network bridge=br{{ item[0] }},mac={{ item[1] }},model=virtio
-      {%   else %}
-      --network bridge=br{{ item[0] }},model=virtio
+      {% for item in network_interfaces %}
+      {%   if item.vlan is defined %}
+      {%     if item.mac is defined %}
+      --network bridge=br{{ item.vlan }},mac={{ item.mac }},model=virtio
+      {%     else %}
+      --network bridge=br{{ item.vlan }},model=virtio
+      {%     endif %}
       {%   endif %}
       {% endfor %}