*) mod_http2: new directive "H2HeaderStrictness" to control the compliance

  *) mod_http2: new directive "H2HeaderStrictness" to control the compliance
     level of header checks as defined in the HTTP/2 RFCs. Default is 7540.
     9113 activates the checks for forbidden leading/trailing whitespace in
     field values (available from nghttp2 v1.50.0 on).

   - source sync with github version
   - fix for keepalive idle wait in mpm_worker setup
   - ensuring EOS when secondary connection has been handled
   - fixed race in late input EOS arrival when stream was
     already scheduled for execution.

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@1904269 13f79535-47bb-0310-9956-ffa450edef68