Upgrade from 1.11.1 to 1.11.2.

<ChangeLog>

*) Change: now nginx always uses internal MD5 and SHA1 implementations;

the --with-md5 and --with-sha1 configure options were canceled.

*) Feature: variables support in the stream module.

*) Feature: the ngx_stream_map_module.

*) Feature: the ngx_stream_return_module.

*) Feature: a port can be specified in the "proxy_bind", "fastcgi_bind",

"memcached_bind", "scgi_bind", and "uwsgi_bind" directives.

*) Feature: now nginx uses the IP_BIND_ADDRESS_NO_PORT socket option

when available.

*) Bugfix: a segmentation fault might occur in a worker process when

using HTTP/2 and the "proxy_request_buffering" directive.

*) Bugfix: the "Content-Length" request header line was always added to

requests passed to backends, including requests without body, when
using HTTP/2.

*) Bugfix: "http request count is zero" alerts might appear in logs when

using HTTP/2.

*) Bugfix: unnecessary buffering might occur when using the "sub_filter"

directive; the issue had appeared in 1.9.4.

</ChangeLog>