Iperf 2 support

[rjmcmahon]

Hi All,

It's might be good to adopt iperf 2 as a plugin. There has been a lot of work around latency.

https://sourceforge.net/projects/iperf2/

https://techcommunity.microsoft.com/blog/networkingblog/three-reasons-why-you-should-not-use-iperf3-on-windows/4117876

Bob