windows: do not replace sys.stdout by winstdout

Now we use util.stdout everywhere.

mercurial/windows.py

@@ -171,8 +171,6 b' class winstdout(object):'
             self.close()
             raise IOError(errno.EPIPE, 'Broken pipe')
 
-sys.stdout = winstdout(sys.stdout)
-
 def _is_win_9x():
     '''return true if run on windows 95, 98 or me.'''
     try: