Removed plugable schedulers.

Original commit message from CVS:
Removed plugable schedulers.
Removed Scheduler/Manager from elements.
Removed gsttypes.h, rearranged includes.
Removed dependency pad<->element, element<>pipeline, and
various others,  fix includes.
implement gst_pad_get_parent() with gst_object_get_parent()
Make GstTask sefcontained.
Fix _get_state() on GstBin, it did not return ASYNC with a 0
timeout.
Fix endless loop in iterator_fold_with_resync.
diff --git a/gst/gstquery.h b/gst/gstquery.h
index 7d5fdb0..5c72458 100644
--- a/gst/gstquery.h
+++ b/gst/gstquery.h
@@ -107,6 +107,9 @@
 
 struct _GstQueryClass {
   GstMiniObjectClass mini_object_class;
+  
+  /*< private > */
+  gpointer _gst_reserved[GST_PADDING];
 };
 
 void            _gst_query_initialize          (void);