v0.8.1

• Major request handler performance improvement. Benchmarks suggest number of
  requests/s improved by more than 50% for common GET requests!
  We now avoid queuing, buffering and wrapping incoming requests in promises
  when we're below limits and instead can directly process common requests.
  (#291, #292, #293, #294 and #296 by @clue)

• Fix: Fix concurrent invoking next middleware request handlers
  (#293 by @clue)

• Small code improvements
  (#286 by @seregazhuk)

• Improve test suite to be less fragile when using ext-event and
  fix test suite forward compatibility with upcoming EventLoop releases
  (#288 and #290 by @clue)