v0.4.0

Imported release from original tag date 2021-11-23.

We are excited to announce the official release of Framework X to the public! 🎉🚀
This release includes exciting new features such as full compatibility with PHP 8.1,
improvements to response handling, and enhanced documentation covering nginx,
Apache, and async database usage.

• Feature: Announce Framework X public beta.
  (#64 by @clue)

• Feature: Full PHP 8.1 compatibility.
  (#58 by @clue)

• Feature: Improve AccessLogHandler and fix response size for streaming response body.
  (#47, #48, #49 and #50 by @clue)

• Feature / Fix: Skip sending body and Content-Length for responses with no body.
  (#51 by @clue)

• Feature / Fix: Consistently reject proxy requests and handle OPTIONS * requests.
  (#46 by @clue)

• Add new documentation chapters for nginx, Apache and async database.
  (#57, #59 and #60 by @clue)

• Improve documentation, examples and describe HTTP caching and output buffering.
  (#52, #53, #55, #56, #61, #62 and #63 by @clue)