Added camera object & proper auth stuff

* More info in todo & todo list
* Migrate type checking to lodash
* Changed `overrideUrl` to just `url`
* Added more request types
* Response type based on url extension
* makeReuqest callback now follows Node conventions
* Renamed `getCameras` to just `cameras` (hence evercam.public.cameras)

The Camera test don't assert anything, they just test the right URL was
called. This is based on the assumption that 'reuqest' lib works, and
the public test not fail. Might chnage that later