Usage: "bash create-ns.sh [-andc] [command [command parameters]]"

• -a|--any: Use any existing NS without creating a new one (Interactive selection if omitted)
• -n|--new: Create a new NS, even if others exist
• -d|--detach: Detach instead of entering namespace
• -c|--config-file: Use a config file for Uplink/IP/Gateway (Interactive entry if omitted)

Config file structure:

uplink="eno1"
ip="192.168.1.10/24"
gateway="192.168.1.1"