Creating netdev

Creating netdev

[Feature]       Filled stubs for creating netdev (create_netdev_phys,
                create_netdev_macvlan, create_netdev_veth)
[Cause]         N/A
[Solution]      Manage netdev through netlink interface
[Verification]  Build, install, run vasum-server,
                create zone (vasum-cli create_zone zone1),
                start zone (vasum-cli start_zone zone1),
                move interface f.e. p2p1 to zone (vasum-cli create_netdev_phys zone1 p2p1)
                enter to zone (lxc-console -n zone1 --lxcpath=/usr/local/share/.zones -t 0)
                    check interfaces (ifconfig -a)
                do analogous for create_netdev_macvlan and create_netdev_veth

Change-Id: I299d3ebeb8f101a386f5b156dbe79d7779600ef6