Nginx 1.13.9 官方于2018年2月20号发布，在元宵节后我们也及时发布了版本。

主要增加了：http2_push 和 http2_push_preload 指令。

更新日志：

QuoteChanges with nginx 1.13.9 20 Feb 2018

*) Feature: HTTP/2 server push support; the "http2_push" and
"http2_push_preload" directives.

*) Bugfix: "header already sent" alerts might appear in logs when using
cache; the bug had appeared in 1.9.13.

*) Bugfix: a segmentation fault might occur in a worker process if the
"ssl_verify_client" directive was used and no SSL certificate was
specified in a virtual server.

*) Bugfix: in the ngx_http_v2_module.

*) Bugfix: in the ngx_http_dav_module.