Remove 'text-outline' from CSS whitelists

https://www.w3.org/Bugs/Public/show_bug.cgi?id=22149
Merge pull request #23 from foolip/text-outline

Remove 'text-outline' from CSS whitelists
Round the line position to an integer for snap-to-lines cues

https://www.w3.org/Bugs/Public/show_bug.cgi?id=24420
Thank Caitlin Potter
Merge pull request #24 from foolip/thank-caitlin

Thank Caitlin Potter
Make VTTRegion and VTTRegionList not inherit EventTarget

https://www.w3.org/Bugs/Public/show_bug.cgi?id=22962

Thanks Kyle!
Merge pull request #25 from foolip/round-line-position

Round the line position to an integer for snap-to-lines cues
Merge pull request #26 from foolip/no-eventtarget

Make VTTRegion and VTTRegionList not inherit EventTarget
Thank Rick Eyre
Make VTTRegion.scroll an enum ScrollSetting
Remove dead code throwing SyntaxError in enum setters

https://www.w3.org/Bugs/Public/show_bug.cgi?id=22967
https://www.w3.org/Bugs/Public/show_bug.cgi?id=22968
Avoid overlap in a regions example

https://www.w3.org/Bugs/Public/show_bug.cgi?id=23267
Make TextTrack.regions readonly

https://www.w3.org/Bugs/Public/show_bug.cgi?id=22963
Merge pull request #30 from foolip/readonly-regions

Make TextTrack.regions readonly
Merge pull request #27 from foolip/thank-rick

Thank Rick Eyre
Merge pull request #28 from foolip/enum-syntax-error

Make VTTRegion.scroll an enum ScrollSetting

Remove dead code throwing SyntaxError in enum setters
https://www.w3.org/Bugs/Public/show_bug.cgi?id=22967
https://www.w3.org/Bugs/Public/show_bug.cgi?id=22968
Merge pull request #29 from foolip/overlapping-regions

Avoid overlap in a regions example
Let VTTCue have a direct region member instead of a regionId string

https://www.w3.org/Bugs/Public/show_bug.cgi?id=24380
Remove the VTTRegion.track and .id attributes

https://www.w3.org/Bugs/Public/show_bug.cgi?id=24380

There are still uses of the region identifier concept to clean up,
in the parser and in getRegionById().
Remove the extensions to the TextTrack interface

https://www.w3.org/Bugs/Public/show_bug.cgi?id=24380

With a direct association between cues and regions, the text track
itself doesn't need to know about regions, simplifying the API.