Support Geneve traffic in binary-search

[links84]

We were able to get geneve traffic to work on openstack with trex profile.
Since adding this functionality in trafficgen requires some design changes, We can discuss how we can implement this.

[pradiptapks]

Challenges:

1. Currently, the Trafficgen code doesn't understand the encapsulated packets, although we hardcoded the scapy stream (http://pastebin.test.****.com/981112), the existing binary search doesn't evaluate the proper line rate. It looks like the teaching packets failed in the reverse path.
2. In the manual test scenario with Trex, we explicitly defined the scapy streams and executed a dedicated Trex server port defining the scapy header with appropriate outer mac and IP addresses.
3. The traffic needs a similar capability instead of executing the stream in all Trex ports.
4. The existing Trafficgen flows logic may apply in the inner header as the outer header is expected to be defined statically.
5. Sample failure test results for reference:
   http://pbench.perf.***.***.***.*****.com/results/perf122.perf.lab.eng.bos.redhat.com/geneve-experiment/trafficgen_Geneve-Unidirectioanl-Test_tg:trex-profile_pf:profile.json_ml:0,0.02_tt:bs_2021-07-09T12:20:56/