* caddyhttp: Reject 0-RTT early data in IP matchers and set Early-Data header when proxying
See RFC 8470: https://httpwg.org/specs/rfc8470.html
Thanks to Michael Wedl (@MWedl) at the University of Applied Sciences St. Poelten for reporting this.
* Don't return value for {remote} placeholder in early data
* Add Caddyfile support