Pass rollbar client settings directly to snippet

..instead of a 'whitelist' of just a few, pass any client settings given to the smoke_detector provider config.

- [x] Update README
![i win](http://api.ning.com/files/ChrUHISpgHJ0JKGuQZIj-lNMFpZ9PO*UsoXMYXX0sZHIreot2WmvQXjMByPgNJKEx55ygnJhzFHHUVJp6PBGntpQ5rne*tjU/1305523587250.png)