Add support for devcontainers

[Apreche]

The VSCode Tailscale extension does not seem to work from within a VSCode devcontainer.

Tailscale is installed inside the devcontainer. I installed it using the tailscale devcontainer feature

However, tailscale isn't running inside the container. I can't seem to make it run in the container either. If I do tailscale up in the terminal it says it can't connect to tailscaled. I can't do sudo systemctl start tailscaled because the container doesn't have systemd. It's a devcontainer. I tried to start tailescaled within the container various other ways, to no avail.

I'd really like to get this working because I strongly prefer to do all my development inside of devcontainers.