Changes with nginx 1.15.0                                        05 Jun 2018

    *) Change: the "ssl" directive is deprecated; the "ssl" parameter of the
       "listen" directive should be used instead.

    *) Change: now nginx detects missing SSL certificates during
       configuration testing when using the "ssl" parameter of the "listen"
       directive.

    *) Feature: now the stream module can handle multiple incoming UDP
       datagrams from a client within a single session.

    *) Bugfix: it was possible to specify an incorrect response code in the
       "proxy_cache_valid" directive.

    *) Bugfix: nginx could not be built by gcc 8.1.

    *) Bugfix: logging to syslog stopped on local IP address changes.

    *) Bugfix: nginx could not be built by clang with CUDA SDK installed;
       the bug had appeared in 1.13.8.

    *) Bugfix: "getsockopt(TCP_FASTOPEN) ... failed" messages might appear
       in logs during binary upgrade when using unix domain listen sockets
       on FreeBSD.

    *) Bugfix: nginx could not be built on Fedora 28 Linux.

    *) Bugfix: request processing rate might exceed configured rate when
       using the "limit_req" directive.

    *) Bugfix: in handling of client addresses when using unix domain listen
       sockets to work with datagrams on Linux.

    *) Bugfix: in memory allocation error handling.