0.9.4 (unstable)

* Bin: Added signals.
  (José Alburquerque)
* Bus: Added pop() methods. 
* Pad: Added  get_pad_template_caps(), alloc_buffer(),
  alloc_buffer_and_set_caps(), get_range(), proxy_getcaps(), push, push_event(),
  send_event(), event_default(), query, peer_query(), query_default(),
  get_query_types(), get_query_types_default(), get_internal_links(),
  get_internal_links_default(), chain().
  Added have_data signal.
  (Siavash Safi. Bug #517208.)
* Element: Added get_factory().
  (José Alburquerque)
* Added ElementFactory, Filter, IndexFactory, Parse, Plugin, PluginFeature, 
  Task, UriHandler
  (José Alburquerque)