Enhancement for Invoke-IcingaCheckNetworkInterface Status Checks

[audiocoach]

I think it would ne a nice feature if you can set more than one value for the status checks warning and critical thresholds. In my opinion there is more than one state which could be considered warning or critical. E.G. for the IfConnectionStatus the following could be considered warning or critical:

• Disconnected
• HardwareMalfunction
• MediaDisconnected
• Unknown
• …
  As an alternative and maybe easier to implement: Add a negate switch, so that all states not matching the defined value are critical.