JavaScript Translation. Modifies the description to make it language agnostic.

• Side note: unless I'm missing something, the Python tests seem to care about the parity of the array length - isn't that an irrelevant attribute? The ratio of negatives to positives is, imo, the key attribute. The parity affects nothing - you're not dividing by 2. So for the fixed tests, I did not group things by parity like the Python version.