Updated tests to check for either ifconfig/iproute2
Updated tests to check for either ifconfig/iproute2

rackerlabs/openstack-guest-agents-unix,rackerlabs/openstack-guest-agents-unix,joejulian/openstack-guest-agents-unix,joejulian/openstack-guest-agents-unix,joejulian/openstack-guest-agents-unix,rackerlabs/openstack-guest-agents-unix