gst/pygstminiobject.c: thread safe handling of mini-objects

gst/pygstminiobject.c: thread safe handling of mini-objects

Original commit message from CVS:
* gst/pygstminiobject.c:
thread safe handling of mini-objects
* codegen/codegen.py: (GstMiniObjectWrapper.constructor_tmpl):
let's not forget to wrap the MiniObject :)
* gst/gst-types.defs:
* gst/gst.defs:
Always keep up to date with the core
* gst/gstelement.override:
override for gst_element_query_position
* gst/pygstminiobject.c:
* gst/pygstminiobject.h:
* gst/gst.override:
PyGstMiniObject now properly wrap GstMiniObject and are referenced in a
global hash table