Test case override of traffic profile settings.

Test case override of traffic profile settings.

JIRA: YARDSTICK-1298

Allow the test case file e.g. "tc_prox_baremetal_l2fwd-4.yaml"
settings to override the values in the traffic_profile file
e.g. "prox_binsearch.yaml"

This is done by adding the "traffic_config" section to the
"options" section in the "test case file".

See below :-

  options:
    interface_speed_gbps: 10

    traffic_config:
      tolerated_loss: 0.001
      test_precision: 0.1
      packet_sizes: [64]
      duration: 30
      lower_bound: 0.0
      upper_bound: 100.0

    vnf__0:
      prox_path: /opt/nsb_bin/prox
      prox_config: "configs/handle_l2fwd-4.cfg"
      prox_args:
        "-t": ""

    tg__0:
      prox_path: /opt/nsb_bin/prox
      prox_config: "configs/gen_l2fwd-4.cfg"
      prox_args:
        "-e": ""
        "-t": ""

Precedence of the traffic settings.

1. Values provided in the "traffic_config" section, inside
   the "options" section, of the test case file
2. values provided in the "traffic_profile" section of the
   traffic_profile file

Change-Id: I6b4e123e865c9dab548f9ad28647f95b53410e8f
Signed-off-by: Daniel Martin Buckley <daniel.m.buckley@intel.com>