An extra application preset dir help to organize presets created for special
purposes. Fixes#660760
API: gst_preset_set_app_dir(), gst_preset_get_app_dir()
Original commit message from CVS:
* gst/gstpreset.c:
* gst/gstpreset.h:
Change _get_preset_names API to return a strv with copies. Add
_get_property_names to allow implementations to filter and provide
good default implementation.
Original commit message from CVS:
* gst/gstpreset.c:
Add some comments and TODOs.
* gst/gstpreset.h:
Add padding for future changes.
* plugins/elements/gstqueue.c:
Implement the iface.