lots of little changes, plus two new calls, all backwards compatible!

@hjespers - thanks for the great package. i'm using it in one of my projects and did a little cleanup!

- pass jshint (useful for lots of little reasons)
- new call all() to get an array of all vehicles
- vehicles() and get_vid() are now front-ends to all()
- new call stream() for raw streaming interface
- check error/response.statusCode on all callbacks from request()

questions? please let me know. thanks!