windows: add various missing import

mercurial/windows.py

@@ -8,7 +8,8 b' the GNU General Public License version 2'
 reference.
 """
 
-import msvcrt, sys, os
+from i18n import _
+import errno, msvcrt, os, osutil, re, sys
 nulldev = 'NUL:'
 
 umask = 002