• fixes Timeout vs. KeepAliveTimeout behaviour, see PR 63534 (for trunk now,
  mpm event backport to 2.4.x up for vote).
• Fixes stream cleanup when connection throttling is in place.
• Counts stream resets by client on streams initiated by client as cause
  for connection throttling.
• Header length checks are now logged similar to HTTP/1.1 protocol handler (thanks @mkaufmann)
• Header length is checked also on the merged value from several header instances
  and results in a 431 response.