Changes with nginx 1.13.1 30 May 2017
*) Feature: now a hostname can be used as the "set_real_ip_from" directive parameter.
*) Feature: vim syntax highlighting scripts improvements.
*) Feature: the "worker_cpu_affinity" directive now works on DragonFly BSD. Thanks to Sepherosa Ziehau.
*) Bugfix: SSL renegotiation on backend connections did not work when using OpenSSL before 1.1.0.
*) Workaround: nginx could not be built with Oracle Developer Studio 12.5.
*) Workaround: now cache manager ignores long locked cache entries when cleaning cache based on the "max_size" parameter.
*) Bugfix: client SSL connections were immediately closed if deferred accept and the "proxy_protocol" parameter of the "listen" directive were used.
*) Bugfix: in the "proxy_cache_background_update" directive.
*) Workaround: now the "tcp_nodelay" directive sets the TCP_NODELAY option before an SSL handshake.