Negative size buffers detection. In the past, there were several security issues which resulted in worker process memory disclosure due to buffers with negative size. It looks reasonable to check for such buffers in various places, much like we already check for zero size buffers. While here, removed "#if 1 / #endif" around zero size buffer checks. It looks highly unlikely that we'll disable these checks anytime soon.

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.