Fix file name for ruby vtt test in runtests.js
Fix timestamp-span test to expect the correct # of cues.
Test that we deal with garbage WEBVTT signatures.

I've added a new condition to the flush function so that we don't
incorrectly try to synthesize the end of a WEBVTT signature.
Merge pull request #7 from RickEyre/garbage-webvtt

Test that we deal with garbage WEBVTT signatures.
Clean up comments and state ordering.
Update references to the spec to the lastest editor's draft.
parse cue settings
parse meta headers, parse regions, and factor out parsing of settings