Support for windows

[stereobooster]

Sending PR to keep you update on my progress. Work not done yet.

Current result of runing tests https://gist.github.com/3845607

Windows related issues #17, #18, #9

[stereobooster]

testing win32-process (by @djberg96) to support fork, no luck yet

[djberg96]

The fork implementation was removed in the latest implemenation of win32-process. It was always experimental. Between the addition of Process.spawn in 1.9 and thread programming in general, I just didn't feel it was worth keeping or maintaining. If anything, it should be packaged as a separate lib.

[stereobooster]

ruby -v 
ruby 1.9.3p194 (2012-04-20) [i386-mingw32]

 56) Failure:
test_spawn_redirect_stderr_and_stdout_to_same_fd(NativeSpawnTest) [d:/projects/posix-pawn/test/test_spawn.rb:180]:
<"hello world\n"> expected but was
<"d:/projects/posix-spawn/test/test_spawn.rb:399: warning: cannot close fd before spawn\nhello world \n">.

@luislavena Aren't those warning: cannot close fd before spawn fixed? http://bugs.ruby-lang.org/issues/4798

[luislavena]

@stereobooster sorry, just catching up. Not sure if this project errors are fixed by Ruby bug you linked. Is not clear to me how they relate.

Can you try running this project over latest Ruby and see how it goes?

[stereobooster]

Isn't ruby 1.9.3p194 (2012-04-20) [i386-mingw32] the latest Ruby (on windows)? Or you mean complie latest ruby from trunk?

P.S. There are only 3 those errors, but 95 failed tests. So it's not biggest problem.

[rtomayko]

Closing as stale. Please reopen if we still want to pursue this PR.