[networking] netstat truncates IPv6 addresses

[pmoravec]

netstat -neopa truncates IPv6 addresses. Option -W / -T for net-tools version >=2 / <2 should be added to fix it.

[bmr-cymru]

The real problem here is the need for separate switches for different versions... It's doable but distinctly ugly :-(

[pmoravec]

One option is command switches based on net-tools version, another is collect both commands outputs and either store them, or keep just the relevant one.

In this option, one gotcha is netstat -T on version >=2 has return value zero, so one would have to check netstat_output['output'][0] starting by netstat: invalid option.

[bmr-cymru]

You seem to think our package manager version checks work :-)

I don't like the idea of treating these as separate commands - to the user they're the same data and it's a quirk of distro history that the switches were once different (we can use suggest_filename to force the name to the old name so users will not see any change).

[bmr-cymru]

OK so see also issue #763 - we can do this with the current package manager abstraction but it is eye-wateringly ugly :-)

I'll commit a fix for this issue first since the changes to the policy classes are likely to be extensive. That way downstreams that want to fix the netstat collection can cherry-pick that change without pulling in the rest.