nghttp2 library itself now accept octet header/value pairs,
completely not restricted by HTTP/1 header name/value rule.
The applications may impose restriction about them using
validators.
Now, in nghttp2_on_frame_recv_callback, nva and nvlen in
HEADERS and PUSH_PROMISE frames are always NULL and 0 respectively.
The header name/value pairs are emitted successive
nghttp2_on_header_callback functions. The end of header fields are
signaled with nghttp2_on_end_headers_callback function.
Since NGHTTP2_ERR_PAUSE for nghttp2_on_frame_recv_callback is
introduced to handle header block, it is now deprecated.
Instead, nghttp2_on_header_callback can be paused using
NGHTTP2_ERR_PAUSE.
This commit also changes SPDY's flow control size. Previously,
the size for SPDY is the same amount of bytes with HTTP/2.
For example, --frontend-http2-upstream-window-bits=N,
the window size is 2**N - 1. Now SPDY code uses 2**N.
Remove sorting headers from library code. The application must sort
them if necessary. nghttpx and nghttpd do the sorting of the headers
in stable way if names are equal.
nghttp2_session_client_new2 and nghttp2_session_server_new2 take
additional parameters which specifies session options.
nghttp2_set_option is somewhat crumsy because of type checking.
Now we use nghttp2_opt_set, which specifies individual options with
types. We changed the value of nghttp2_opt, so this change will
require re-compile.
Tatsuhiro Tsujikawa