randomize(probability) {
        for (let i = 0; i < this._width; i++) {
            for (let j = 0; j < this._height; j++) {
                this._map[i][j] = (RNG.getUniform() < probability ? 1 : 0);
            }
        }
        return this;
    }
Fill the map with random values
@param {float} probability Probability for a cell to become alive; 0 = all empty, 1 = all full