NT support

["Howard Chu" <hyc@highlandsun.com>]

Just a heads up, my colleague Jon Leichter has been working on updating the
HEAD stream with the current Cygwin and Mingw stuff. There will be a large
number of patches associated with this effort, but the result is much
cleaner source. (Yes, all those NT-specific extern's in C source files will
go away.)
We will do a preliminary checkin of the NT-specific patches, do a fresh
build on Linux to make sure nothing broke, and finish up with an MSVC build
and any additional patches required to make that work.

  -- Howard Chu
  Chief Architect, Symas Corp.       Director, Highland Sun
  http://www.symas.com               http://highlandsun.com/hyc
  Symas: Premier OpenSource Development and Support