There is no need to cancel timers early if there are other timers blocking
shutdown anyway.  Preserving such timers allows nginx to continue some
periodic work till the shutdown is actually possible.

With the new approach, timers with ev->cancelable are simply ignored when
checking if there are any timers left during shutdown.

It's mostly dead code.  And the idea of thread support for this task has
been deprecated.

    *) Change: the "bl" and "af" parameters of the "listen" directive was
       renamed to the "backlog" and "accept_filter".

    *) Feature: the "rcvbuf" and "sndbuf" parameters of the "listen"
       directive.

    *) Change: the "$msec" log parameter does not require now the
       additional the gettimeofday() system call.

    *) Feature: the -t switch now tests the "listen" directives.

    *) Bugfix: if the invalid address was specified in the "listen"
       directive, then after the -HUP signal nginx left an open socket in
       the CLOSED state.

    *) Bugfix: the mime type may be incorrectly set to default value for
       index file with variable in the name; the bug had appeared in 0.3.0.

    *) Feature: the "timer_resolution" directive.

    *) Feature: the millisecond "$upstream_response_time" log parameter.

    *) Bugfix: a temporary file with client request body now is removed
       just after the response header was transferred to a client.

    *) Bugfix: OpenSSL 0.9.6 compatibility.

    *) Bugfix: the SSL certificate and key file paths could not be relative.

    *) Bugfix: the "ssl_prefer_server_ciphers" directive did not work in
       the ngx_imap_ssl_module.

    *) Bugfix: the "ssl_protocols" directive allowed to specify the single
       protocol only.

    *) Feature: the Sun Studio 10 C compiler support.

    *) Feature: the "proxy_upstream_max_fails",
       "proxy_upstream_fail_timeout", "fastcgi_upstream_max_fails", and
       "fastcgi_upstream_fail_timeout" directives.

    *) Bugfix: the segmentation fault occurred when the signal queue
       overflowed if the "rtsig" method was used; the bug had appeared in
       0.2.0.

    *) Change: correct handling of the "\\", "\"", "\'", and "\$" pairs in
       SSI.

    *) Change: the 10-days live time limit of worker process was
       eliminated. The limit was introduced because of millisecond timers
       overflow.

    *) Bugfix: nginx did run on Linux parisc.

    *) Feature: nginx now does not start under FreeBSD if the sysctl
       kern.ipc.somaxconn value is too big.

    *) Bugfix: if a request was internally redirected by the
       ngx_http_index_module module to the ngx_http_proxy_module or
       ngx_http_fastcgi_module modules, then the index file was not closed
       after request completion.

    *) Feature: the "proxy_pass" can be used in location with regular
       expression.

    *) Feature: the ngx_http_rewrite_filter_module module supports the
       condition like "if ($HTTP_USER_AGENT ~ MSIE)".

    *) Bugfix: nginx started too slow if the large number of addresses and
       text values were used in the "geo" directive.

    *) Change: a variable name must be declared as "$name" in the "geo"
       directive. The previous variant without "$" is still supported, but
       will be removed soon.

    *) Feature: the "%{VARIABLE}v" logging parameter.

    *) Feature: the "set $name value" directive.

    *) Bugfix: gcc 4.0 compatibility.

    *) Feature: the --with-openssl-opt=OPTIONS autoconfiguration directive.