SFC Yardstick test

SFC Yardstick test

Modifications of the SFC Yardstick test

The test creates two chains. One chain blocks HTTP the other one blocks SSH.
We doublecheck that HTTP works in one but not in the other and the same for
SSH.

There are some things that must be modified manually as ODL is not yet ready
for ovs 2.5.90. Here are the instructions:

https://wiki.opnfv.org/display/sfc/Yardstick

Change-Id: Ide6588a682f3491ab58c47ee7335205868c109fc
Signed-off-by: Manuel Buil <manuel.buil@ericsson.com>