[MSE] Spec Updates Published

I have published updates to the Media Source
Extensions<https://dvcs.w3.org/hg/html-media/raw-file/default/media-source/media-source.html>
 spec.

Summary of changes:
Bug 25518 <https://www.w3.org/Bugs/Public/show_bug.cgi?id=25518> - Make
remove() end parameter an unrestricted double.
Bug 25580 <https://www.w3.org/Bugs/Public/show_bug.cgi?id=25580> - Add
informative reference to byte stream format registry.
Bug 24370 <https://www.w3.org/Bugs/Public/show_bug.cgi?id=24370> - Add
TrackDefault object and remove kind/language overloads.

There were a fair amount of changes involved in adding the TrackDefault
object and removing the kind/language overloads. As you will see most of
the algorithmic changes were constrained to the initialization segment
received algorithm. Please file new bugs and don't reopen Bug 24370 if you
find problems with the new text.

Diffs:
https://dvcs.w3.org/hg/html-media/rev/3e8dfccbfded
https://dvcs.w3.org/hg/html-media/rev/01c9e30d71b0

Aaron