Threads: writing via threads pools in event pipe. The "aio_write" directive is introduced, which enables use of aio for writing. Currently it is meaningful only with "aio threads". Note that aio operations can be done by both event pipe and output chain, so proper mapping between r->aio and p->aio is provided when calling ngx_event_pipe() and in output filter. In collaboration with Valentin Bartenev.

make -f misc/GNUmakefile release

the required tools:
*) xsltproc to build CHANGES,
*) xslscript.pl ( http://hg.nginx.org/xslscript ) to build XSLTs
   from XSLScript sources.


make -f misc/GNUmakefile icons

the required tool:
*) netpbm to create Win32 icons from xpm sources.