add `rename' gnulib module

This should fix `rename' on mingw32.

lib/same-inode.h

@@ -0,0 +1,25 @@
+/* Determine whether two stat buffers refer to the same file.
+
+   Copyright (C) 2006, 2009-2011 Free Software Foundation, Inc.
+
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU Lesser General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+#ifndef SAME_INODE_H
+# define SAME_INODE_H 1
+
+# define SAME_INODE(Stat_buf_1, Stat_buf_2) \
+   ((Stat_buf_1).st_ino == (Stat_buf_2).st_ino \
+    && (Stat_buf_1).st_dev == (Stat_buf_2).st_dev)
+
+#endif