*) mod_http2: new configuration directive: ```H2Padding numbits``` to control

  *) mod_http2: new configuration directive: ```H2Padding numbits``` to control
     padding of HTTP/2 payload frames. 'numbits' is a number from 0-8,
     controlling the range of padding bytes added to a frame. The actual number
     added is chosen randomly per frame. This applies to HEADERS, DATA and PUSH_PROMISE
     frames equally. The default continues to be 0, e.g. no padding. [Stefan Eissing]

  *) mod_http2: ripping out all the h2_req_engine internal features now that mod_proxy_http2
     has no more need for it. Optional functions are still declared but no longer implemented.
     While previous mod_proxy_http2 will work with this, it is recommeneded to run the matching
     versions of both modules. [Stefan Eissing]

  *) mod_proxy_http2: changed mod_proxy_http2 implementation and fixed several bugs which
     resolve PR63170. The proxy module does now a single h2 request on the (reused)
     connection and returns. [Stefan Eissing]

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@1854963 13f79535-47bb-0310-9956-ffa450edef68