Fix declaration of iperf_test.bind_port

Signed-off-by: Kevin Constantine <kevin.constantine@gmail.com>
Support --cport and --parallel

When running multiple parallel streams, the specified port number
is incremented for each successive stream.

Signed-off-by: Kevin Constantine <kevin.constantine@gmail.com>
Comment fix: Fix the option associated with iperf_test.bind_port.

No functional change.
Merge branch 'kevinconstantine-master'