Full stream shutdown is now called from stream cleanup handler instead of
explicitly sending frames.

This makes it possible to avoid looping for a long time while working
with a fast enough peer when data are added to the socket buffer faster
than we are able to read and process them (ticket #1431).  This is
basically what we already do on FreeBSD with kqueue, where information
about the number of bytes in the socket buffer is returned by
the kevent() call.

With other event methods rev->available is now set to -1 when the socket
is ready for reading.  Later in ngx_recv() and ngx_recv_chain(), if
full buffer is received, real number of bytes in the socket buffer is
retrieved using ioctl(FIONREAD).  Reading more than this number of bytes
ensures that even with edge-triggered event methods the event will be
triggered again, so it is safe to stop processing of the socket and
switch to other connections.

Using ioctl(FIONREAD) only after reading a full buffer is an optimization.
With this approach we only call ioctl(FIONREAD) when there are at least
two recv()/readv() calls.

    *) Feature: the "wait" parameter in the "include" SSI command.

    *) Feature: the Ukrainian and Byelorussian characters were added to
       koi-win conversion table.

    *) Bugfix: in the SSI.

    *) Bugfix: the proxied request was sent without arguments if the
       request contains "//", "/./", "/../" or "%XX".

    *) Bugfix: the large compressed responses may be transferred not
       completely.

    *) Bugfix: the files bigger than 2G was not transferred on Linux that
       does not support sendfile64().

    *) Bugfix: while the build configuration on Linux the
       --with-poll_module parameter was required; the bug had appeared in
       0.1.8.

    *) Bugfix: on FreeBSD the segmentation fault may occur if the size of
       the transferred file was changed; the bug had appeared in 0.1.5.

    *) Bugfix: on Solaris and Linux there may be too many "recvmsg()
       returned not enough data" alerts.

    *) Bugfix: there were the "writev() failed (22: Invalid argument)"
       errors on Solaris in proxy mode without sendfile. On other platforms
       that do not support sendfile at all the process got caught in an
       endless loop.

    *) Bugfix: segmentation fault on Solaris in proxy mode and using
       sendfile.

    *) Bugfix: segmentation fault on Solaris.

    *) Bugfix: on-line upgrade did not work on Linux.

    *) Bugfix: the ngx_http_autoindex_module module did not escape the
       spaces, the quotes, and the percent signs in the directory listing.

    *) Change: the decrease of the copy operations.

    *) Feature: the userid_p3p directive.

    *) Feature: the --user=USER, --group=GROUP, and --with-ld-opt=OPTIONS
       options in configure.

    *) Feature: the server_name directive supports *.domain.tld.

    *) Bugfix: the portability improvements.

    *) Bugfix: if configuration file was set in command line, the
       reconfiguration was impossible; the bug had appeared in 0.1.1.

    *) Bugfix: proxy module may get caught in an endless loop when sendfile
       is not used.

    *) Bugfix: with sendfile the response was not recoded according to the
       charset module directives; the bug had appeared in 0.1.1.

    *) Bugfix: very seldom bug in the kqueue processing.

    *) Bugfix: the gzip module compressed the proxied responses that was
       already compressed.