* lib: Add nghttp2_error_callback2
* build: Add deprecation warning when spdylay support is enabled
* Switch to clang-format-5.0
* examples: Make client and server work with libevent-2.1.8
* third-party: Update neverbleed
* integration: Fix issues reported by the go vet tool.
* nghttpx: Fix affinity retry
* nghttpx: Fix stalled backend connection on retry
* nghttpx: Cookie based session affinity
* nghttpx: Expose additional TLS related variables to mruby and
accesslog
OBS-URL: https://build.opensuse.org/package/show/devel:libraries:c_c++/nghttp2?expand=0&rev=78
