Preliminary work to cut over to Kohana 2.4

- Kohana::log() -> Kohana_Log::add()
- Kohana::config_XXX -> Kohana_Config::instance()->XXX
- Implement View::set_global in MY_View
- Updated Cache_Database_Driver to latest APIs
- ORM::$loaded -> ORM::loaded()
- Updated item::viewable() to use K2.4 parenthesization

modules/user/controllers/admin_users.php

@@ -265,7 +265,7 @@ class Admin_Users_Controller extends Admin_Controller {
     if ($valid) {
       $new_name = $form->edit_group->inputs["name"]->value;
       $group = group::lookup_by_name($name);
-      if ($group->loaded) {
+      if ($group->loaded()) {
         $form->edit_group->inputs["name"]->add_error("in_use", 1);
         $valid = false;
       }