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/comment/tests/Comment_Event_Test.php

@@ -27,6 +27,6 @@ class Comment_Event_Test extends Unit_Test_Case {
     $album->delete();
 
     $deleted_comment = ORM::factory("comment", $comment->id);
-    $this->assert_false($deleted_comment->loaded);
+    $this->assert_false($deleted_comment->loaded());
   }
 }