Suggest the [webvtt] prefix for email to public-tt

Per request from Nigel Megitt.
Merge pull request #145 from foolip/public-tt-prefix

Suggest the [webvtt] prefix for email to public-tt
Teach publish.sh to publish TTWG snapshots
Use cvs update -C to discard any local changes
Include the spec URL in bug reports

Per request from Nigel Megitt, to track feeback on the snapshot.
Write a new bug-filing tool
Merge pull request #147 from foolip/publish-snapshot

Teach publish.sh to publish TTWG snapshots
Merge pull request #149 from foolip/bug-ui

Write a new bug-filing tool
Add a note to snapshots pointing to the most recent CG draft
Tweak the style of the snapshot note to be more distinct
Drop "This is a snapshot!" from banner
Teach format.py that <br> has no end tag
Merge pull request #150 from foolip/hasendtag

Teach format.py that <br> has no end tag
Merge pull request #146 from foolip/snapshot-note

Add a note to snapshots pointing to the most recent CG draft
Make the URL work again for CG version of spec.

This is likely a typo that led to double declaration of specUrl and
broke the URL for CG bugs.
Make the overlay work again.

The brackets in this if statement weren't quite right.
Merge pull request #152 from silviapfeiffer/showOverlay

Make the overlay work again.
Merge pull request #151 from silvia/fixDeclaration

Make the URL work again for CG version of spec.
Revert "Make the overlay work again."

This reverts commit e5ef88e3ecff89cc72649d0548efbdb0ae79f4c0.

The overlay was made to be visible only in the static snapshot, and to be shown
only after the script has checked that it hasn't already been dismissed, to
prevent it appearing and disappearing briefly during load.

The reverted change made it such that the script only runs under ReSpec, which
makes the overlay always visible in the static spec and impossible to dismiss.
Indent a comment which may have made this look more wrong than it is