Feature Add support for static IP Addr and display MAC Addr

[wambs]

This functionality supports the following:

1. Display the WiFI MAC Addr on the settings network configuration section
2. Support static IP addr in settings network configuration and backup networks.

Tested both the main and backup networks, seems to work well.
I created a git branch in my forked repository. Not sure if I did it correctly.
I think I pulled in all my changes in this pull request, including the Group PID stuff.

These files were changed:
modified: main/config_server.c
modified: main/config_server.h
modified: main/web/src/homepage.html
modified: main/web/src/main.js
modified: main/wifi_mgr.c
modified: main/wifi_mgr.h
modified: main/wifi_network.c

[meatpiHQ]

@wambs There are too many changes unrelated to static IP.