Support both older and newer versions of Netcat

[MaxLap]

Hello. On Ubuntu 16.04, nc doesn't have a -N parameter. But on 20.04, it seem to have it. Both land in the same if of the daemon-wrapper script.

This PR does a grep in the output of nc -h to check if there is a parameter named -N or not, and use the command based on it.

This could possibly replace the whole list of ifs, but that's not something I can verify. I just know that in the case where we don't really know what the OS is, making an educated guess seems like a better idea than just forcing one of the two choice.

Regards, and thanks for this project!