kubernetes web tty demo with Deno

1. intended to be served from inside the cluster
2. serves a basic xterm.js which is plugged into a particular pod
3. uses websockets, which (with Deno) means that --cert must be provided as below
4. uses websocketstream, so you also need --unstable
5. is very insecure, do not serve on the internet
6. error handling is bad

you can run like this:

deno run -A --unstable --cert /var/run/secrets/kubernetes.io/serviceaccount/ca.crt mod.tsx