Adds a shuffle method in array prototype.

:monkey: jojoShuffle.js

Array.prototype.shuffle = function() {
  return this
    .reduce(
      ([result, rest]) => {
        const random = (Math.random() * rest.length) >> 0;
        return [
          result
            .concat(rest[random]),
          rest
            .slice(0, random)
            .concat(rest.slice(random + 1))
        ];
      },
      [[], this.slice()]
    )[0]
};