netdetect: Let's save the resulting file

Let's print it to the console and save it in a file.

Typical output is:

Saving results in ProLiantDL360pGen8655651B21-HP-CZ3323FDV8d8-9d-67-1a-41-7c.perf.hw
[...]
('network', 'tcp_bench', 'conf', '87380/16384/16384'),
('network', 'tcp_bench', 'bw', '110.51')]

Note the .perf.hw extension.
netdetect: If a single server is present, let's exit

There is no interest testing a single server....
netdetect: Daemon option doesn't always exist

On some older release of netperf, the -D option doesn't exist.
As we are part of a thread, this is not a fatal issue.

netserver is so running in background.
netdetect: s/killall/pkill/

I don't have killall on the wheezy
netdetect: Adding port information to netperf

Former commit did remove the port by mistake, let's put it back again.
netdetect: Don't search for perfect timing

When parsing netperf output, don't try to search x.00 value as sometimes
it's ending a little bit later. So search x. is enough.