nucleotides test and example in coffeescript

I squashed the commits together into one and renamed the main file. I think I have done everything correctly, but if there is something else let me know :)
I think I had tried that at one point, but you can't use `not in` in a Javascript array, can you? I have only seen that in Python. I just tried this line again on here and it breaks half of the tests.
With that said, if there is a better way to write lines 10-12 I would love to know. I'm sure my way is not at all as condensed as it could be.