First step:  Generate all the JSON goop regardless of --json or not.
Client and server exchange full results if --get-remote-results flag is set.

The form of these results is essentially the JSON that's sent if
the --json flag is sent.  We don't exchange these by default because
they can be a fairly significant amount of data for long-running
tests or over slow links (several KB for even a default 10-second test).
Merge branch 'feature/server-stats' of github.com:/esnet/iperf into feature/server-stats