uri: add filename_to_uri to bindings
uri: add filename_to_uri to bindings

lubosz/gst-python,freedesktop-unofficial-mirror/gstreamer__gst-python,lubosz/gst-python,pexip/gst-python,GStreamer/gst-python,GStreamer/gst-python,lubosz/gst-python,freedesktop-unofficial-mirror/gstreamer__gst-python,alessandrod/gst-python,freedesktop-unofficial-mirror/gstreamer__gst-python,pexip/gst-python,GStreamer/gst-python,alessandrod/gst-python,alessandrod/gst-python,pexip/gst-python