*) Fixed spelling of "endianness", and called it "byte ordering" in the
   user visible part.

*) Fixed return type of ngx_strerror_init().

*) Fixed a harmless error in spelling of "Connection: close" when computing
   the response header length.

*) Style.

*) Added code to look up Google perftools in /opt/local/, for MacPorts.

*) Win32: disallowed access to various non-canonical name variants.

   This includes trailings dots and spaces, NTFS streams (and short names, as
   previously checked).  The checks are now also done in ngx_file_info(), thus
   allowing to use the "try_files" directive to protect external scripts.

*) Win32: normalization of trailing dot inside uri.

   Windows treats "/directory./" identical to "/directory/".  Do the same
   when working on Windows.  Note that the behaviour is different from one
   with last path component (where multiple spaces and dots are ignored by
   Windows).

*) Win32: uris with ":$" are now rejected.

   There are too many problems with special NTFS streams, notably "::$data",
   "::$index_allocation" and ":$i30:$index_allocation".

   For now we don't reject all URIs with ":" like Apache does as there are no
   good reasons seen yet, and there are multiple programs using it in URLs
   (e.g. MediaWiki).

In case of EMFILE/ENFILE returned from accept() we disable accept events,
and (in case of no accept mutex used) arm timer to re-enable them later.
With accept mutex we just drop it, and rely on normal accept mutex handling
to re-enable accept events once it's acquired again.

As we now handle errors in question, logging level was changed to "crit"
(instead of "alert" used for unknown errors).

Note: the code might call ngx_enable_accept_events() multiple times if
there are many listen sockets.  The ngx_enable_accept_events() function was
modified to check if connection is already active (via c->read->active) and
skip it then, thus making multiple calls safe.

This allows to run nginx with "master_process off" under Windows.

POSIX doesn't require it to be defined, and Debian GNU/Hurd doesn't define
it.  Note that if there is no MAX_PATH defined we have to use realpath()
with NULL argument and free() the result.

Found by Veracode.