test: qdisc_prio_hol - latency testing via {TCP.UDP}_RR

This is an extention to tcp_upload_prio, that uses TCP_RR and UDP_RR
for measuring the latency, based on feedback from Eric Dumazet
and Tom Herbert.

This should be considered a experimental test as it is still
under development.

Some results will be published under:
 http://people.netfilter.org/hawk/qdisc/experiment01/

Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>