windows: break import cycle with util

mercurial/windows.py

@@ -8,7 +8,7 b' the GNU General Public License version 2'
 reference.
 """
 
-from util import Abort
+import util
 from i18n import _
 import errno, msvcrt, os, osutil, re, sys
 nulldev = 'NUL:'
@@ -228,7 +228,7 b' def statfiles(files):'
 
 def getuser():
     '''return name of current user'''
-    raise Abort(_('user name not available - set USERNAME '
+    raise util.Abort(_('user name not available - set USERNAME '
                   'environment variable'))
 
 def username(uid=None):