Media Source Extension Remarks:
- changed appending to updating (and related events)
- Needs to know if a segment is a media segment or an initialization segment in advance
- asynchronous parsing of the media segments
- needs a parsing before playback
- segment manipulation as a playback/playlist controller: entirely in JS (seamless ???)
- implement MSE on top of DASH ?

TODO:
 - out-of-order append
 - out-of-order erroneous append (media segment before init segment)
 - check updating status: append before updating is back to 0 (too many downloads at the same time)
 - muxed audio/video in one sourcebuffer
 - multiple sourcebuffers
 - MPEG-2 TS
 - timestampOffset
 - multiple audio
 - multiple video
 - text tracks
 - append with complete overlap
 - append with start overlap
 - append with end overlap
 - append with middle overlap
 - append with network error
 - append with decode error
 - removeSourceBuffer
 - endOfStream
 - appendStream
 - memory leaks (finalize JS objects)
 - appending multiple media fragments 
 - SVC ?
 - HEVC ?
 - EventTarget
 - GetSLP return Buffer too small & ch_buffer_off / ch_buffer_on
 - Continuity in merge process
 - detect/react when first append is not an init segment.