Added basic throughput tests. additionally
- updated file handling (moved from MR !22 (closed) due to final rework)
- added 2 new clients Test is on WAN and LAN side (where is iperf server located) and client is run always on DUT. Testing if speed is above 400 Mbps. Measuring for 60 seconds, with 10s sample time. If any value withing the sampled data is under 400 Mbps, Warning is risen. If average speed is under 400 Mbps, test is failed.