[MSE] Spec updates published

I have posted more changes 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 21170 <https://www.w3.org/Bugs/Public/show_bug.cgi?id=21170> - Remove
'stream aborted' step from stream append loop algorithm.
Bug 21171 <https://www.w3.org/Bugs/Public/show_bug.cgi?id=21171> - Added
informative note about when addSourceBuffer() might throw an
QUOTA_EXCEEDED_ERR exception.
Bug 20901 <https://www.w3.org/Bugs/Public/show_bug.cgi?id=20901> - Add
support for 'continuation' and 'timestampOffset' abort modes.
Bug 21159 <https://www.w3.org/Bugs/Public/show_bug.cgi?id=21159> - Rename
appendArrayBuffer to appendBuffer() and add ArrayBufferView overload.
Bug 21198 <https://www.w3.org/Bugs/Public/show_bug.cgi?id=21198> - Remove
redundant 'closed' readyState checks.

Diffs:
https://dvcs.w3.org/hg/html-media/rev/dcd406812201

Aaron