Fixed netsh cmd silent failure.

The netsh command for secondary network adapters was using an emtpy string for the adapter name when running the netsh command causing it to silently fail. This change fixes the cmd so it uses the net_connection_id which contains the proper adapter name, i.e. "Local Area Connection"
Merge pull request #97 from WinRb/fix-netsh-cmd

Fixed netsh cmd silent failure.