restapi: Arbitrary vlan device name

1. base_interface and vlan_id property will be received on GET
VdsNetworkInterface.
2.Changes in "setupnetworks" ACTION-
- If the base_interface is specified, it will be used instead of
determining it from the device name. (The device name will be ignored).
- If not, the base_interface name will be determined from the device name
as before. (This should be done to keep backward compatibility).

See: http://www.ovirt.org/Feature/ArbitraryVlanDeviceName#REST_Api

Change-Id: I2b0a42c3f666e408f336f3475903062e9a80a952
Bug-Url: https://bugzilla.redhat.com/1091863
Bug-Url: https://bugzilla.redhat.com/999975
Signed-off-by: Alona Kaplan <alkaplan@redhat.com>