Wait until we're connected to the Internet.
The Internet may be behind a captive portal, so let's wait for that.
If you are using Arch Linux, just
makepkg and use pacman to install.
If not, you're on your own (patches welcome).
sudo systemctl enable --now wait-online after installation to activate.
This service will be ordered before
network-online.target, so your services needing Internet access will be started at the correct time.
Command line usage
check-online will check if we are connected to the Internet and notify
wait-online. This is the service script.
wait-online will wait until we are connected to the Internet (need