Log Message:
nghttp2: updated to 1.27.0

nghttp2 v1.27.0
build: Fixed accidental compiler flags concatenation for MSVC
build: Reduce libxml2 version requirement to 2.6.26
asio: Support for Windows / MinGW
h2load: Print out h2 header fields with --verbose option
nghttpx: Send non-final response to HTTP/1.1 or HTTP/2 client only