Add vlan-raw-device option to interface (Debian)

Add "vlan-raw-device" option to Debian interface template.

As described in documentation if you are NOT using interface name like "ethX.Y" but "vlanY"  (where  Y is VLAN ID) you need to provide physical interface to use with vlan-raw-device option.

https://wiki.debian.org/NetworkConfiguration#Howto_use_vlan_.28dot1q.2C_802.1q.2C_trunk.29_.28Etch.2C_Lenny.29