Drop the local [BIDI] reference

It has been merged into specref:
https://github.com/tobie/specref/pull/141
Refer to DOM as a standard

For consistency with Encoding/HTML and because DOM calls itself a standard.
Merge pull request #164 from foolip/dom-standard

Refer to DOM as a standard
Merge pull request #163 from foolip/bidi-ref

Drop the local [BIDI] reference
Remove one layer of "WebVTT cue settings" sections

The duplicate section title resulted in a section id #webvtt-cue-settings-1
Run format.py
Remove dependency links from the snapshot spec, to preempt objections

https://www.w3.org/Bugs/Public/show_bug.cgi?id=27142
Merge pull request #166 from foolip/remove-snapshot-links

Remove dependency links from the snapshot spec, to preempt objections
Merge pull request #165 from foolip/webvtt-cue-settings-1

Remove one layer of "WebVTT cue settings" sections
Merge commit '7804a6f57e39fe2a8aa111d20af3c49141ab37a2' into position-size-align
Merge commit 'd88b6bdae4cec3a1ce36abb91f32a0ef083ce819' into position-size-align

Conflicts:
	webvtt.html