API tests

After discussion on #42, decided to give this a whack.

This is a start, and should not be considered the _actual_ PR, as I'd like to find out the maintainers' thoughts on this approach. Here I am referring to the EARL stuff, and whether I need IDs and all the other stuff to be doing it "right." 

This set of tests doesn't do much to coverage yet at this point, as they really only hit a few lines of argument count checking... the error case of too few arguments will never be correctly executed, as `callback` is usually required, which by definition can't be populated if the argument count is 0.

Also, I am not exercising any of the `options`.