r2909, r2910, r2922, r2923, r2924, r2925, r2929:

various win32 fixes:

*) use no-threads for Unix builds only
*) Win32 returns ERROR_PATH_NOT_FOUND instead of ERROR_FILE_NOT_FOUND
*) add trailing zero to a file name in ngx_win32_rename_file()
*) fix logging in ngx_win32_rename_file()
*) allow shared memory segments more than 4G
*) fix memory leak in successful case
*) log shared memory name in failure case
*) test that zone has the same addresses in different processes
*) add drive letter for Win32 root path
*) log GetExitCodeProcess()'s errno
*) test premature process termination
*) fix debug logging
*) exit if no workers could not be started
*) do not quit old workers if no new workers could not be started
*) a signaller process should stop configuration processing just after
   it is able to get pid file, this allows to not open log files, etc.
*) win32 master process had aready closed listening sockets

instead, do chdir inside Makefile

options as --with-zlib=../zlib-1.2.3.  It seems there is no common way
to learn the current directory in Win32 make's: although nmake has MAKEDIR
variable, nevertheless Borland make's MAKEDIR is the directory where make
is installed, and OpenWatcom wmake has no MAKEDIR at all.

    *) Feature: the IMAP/POP3 proxy supports STARTTLS and STLS.

    *) Bugfix: the IMAP/POP3 proxy did not work with the select, poll, and
       /dev/poll methods.

    *) Bugfix: in SSI handling.

    *) Bugfix: now Solaris sendfilev() is not used to transfer the client
       request body to FastCGI-server via the unix domain socket.

    *) Bugfix: the "auth_basic" directive did not disable the
       authorization; the bug had appeared in 0.3.11.

    *) 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.