*) core/mod_http: use RESPONSE meta buckets and a new HTTP/1.x specific

  *) core/mod_http: use RESPONSE meta buckets and a new HTTP/1.x specific
     filter to send responses through the output filter chain.
     Specifically: the HTTP_HEADER output filter and ap_send_interim_response()
     create a RESPONSE bucket and no longer are concerned with HTTP/1.x
     serialization.
     A new HTTP1_RESPONSE_OUT transcode filter writes the proper HTTP/1.x
     bytes when dealing with a RESPONSE bucket. That filter installs itself
     on the pre_read_request hook when the connection has protocol 'http/1.1'.

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@1899648 13f79535-47bb-0310-9956-ffa450edef68