appsrc: Add support for custom GstSegment
Add property "handle-segment-change" for user to allow pushing custom segment event. For now, this property can work only for time format GstSegment. This property can be useful in case application controls timeline of stream such as there is timestamp discontinuity but playback is expected to be continuous. Multi-period scenario of MPEG-DASH is an example of this use case.
Closes: #274 (closed)
Depends on gstreamer!490 (merged)