make initgroups module a stub on non-UNIX system, should fix the

Win32 build

lib/Components/initgroups/initgroups.c

@@ -13,6 +13,8 @@
 
 #include "Python.h"
 
+#if defined(__unix__) || defined(unix)
+
 #include <grp.h>
 #include <sys/types.h>
 #include <unistd.h>
@@ -40,6 +42,16 @@ static PyMethodDef InitgroupsMethods[] = {
 	{NULL,		NULL}
 };
 
+#else
+
+/* This module is empty on non-UNIX systems. */
+
+static PyMethodDef InitgroupsMethods[] = {
+	{NULL,		NULL}
+};
+
+#endif /* defined(__unix__) || defined(unix) */
+
 void
 initinitgroups()
 {