SKID-8: Create a networking library

[hark130]

There's barely any JQS line items requiring network programming. Only two have any sort of "networking" mention. Only one has a legitimate programming (as opposed to "usage") objective: a SOCK_RAW BSD socket objective.

So what do we do? Design and implement a "helper" library for common "networking" functions.

Online Resources:

• https://www.thegeekstuff.com/2011/12/c-socket-programming/
• https://www.geeksforgeeks.org/socket-programming-cc/#
• https://www.binarytides.com/socket-programming-c-linux-tutorial/
• https://github.com/codeplea/Hands-On-Network-Programming-with-C
• https://beej.us/guide/bgnet/

[hark130]

I never did document the "a SOCK_RAW BSD socket objective". I'm going to:

• Write a dedicated issue for "10.1 Describe ... and demonstrate ... networking facilities"
• Finish the networking module on this branch
• Merge this branch
• Start/finish work on the "10-1" branch
• Go back to #4

[hark130]

Good notes on uses for SOCK_RAW:

• https://squidarth.com/networking/systems/rc/2018/05/28/using-raw-sockets.html
• https://austinmarton.wordpress.com/2011/09/14/sending-raw-ethernet-packets-from-a-specific-interface-in-c-on-linux/
• https://www.opensourceforu.com/2015/03/a-guide-to-using-raw-sockets/
• https://marcocetica.com/posts/socket_tutorial_part2/