Run vtt.js on PhantomJS from Node.

- Created NodeVTT which runs VTT things on PhantomJS from Node.
- Cue2Json now utilizes the ParserRunner.

With this we can scrap the mocha-phantomjs code. Mocha-phatomjs is good, but lacks the flexibility that comes with running our tests in NodeJS instead of solely on PhantomJS. We can revert back to using our old test harness with a few tweeks.

We can also flesh out NodeVTT a little bit  more and it can become something that people can really use with Node and npm.

Fixes #146.