The typefind function now returns a GstCaps structure instead of a gboolean. modified...

The typefind function now returns a GstCaps structure instead of a gboolean. modified some plugins to this new behaviour

Original commit message from CVS:
The typefind function now returns a GstCaps structure instead of a gboolean.
modified some plugins to this new behaviour
Fixed autoplugging for the mpg123 case. When an element is selected in
autoplugging and the caps do not match, another element is selected until the
caps match. only examples/autoplug works because gstmediaplay uses a threaded
setup that does not seem to work with the current scheduling.