Use PhantomJS binary path from phantomjs package.

Fixes #7.
Upgrade tests and dev dependencies.

- Convert tests to JavaScript; CoffeeScript 1.7 made this less automatic, so might as well.
- Upgrade to latest JSHint.
- Lint the test files.
Upgrade PhantomJS minimum to 1.9.7.

This made the output a decent bit nicer, yay!
Fix WTFPL license usage.

See http://programmers.stackexchange.com/q/149050/13312 which explains http://www.wtfpl.net/faq/.
Travisify.