function setupInfinite(slideArray) {
        var _options2 = options,
            infinite = _options2.infinite;


        var front = slideArray.slice(0, infinite);
        var back = slideArray.slice(slideArray.length - infinite, slideArray.length);

        front.forEach(function (element) {
            var cloned = element.cloneNode(true);

            slideContainer.appendChild(cloned);
        });

        back.reverse().forEach(function (element) {
            var cloned = element.cloneNode(true);

            slideContainer.insertBefore(cloned, slideContainer.firstChild);
        });

        slideContainer.addEventListener(prefixes.transitionEnd, onTransitionEnd);

        return slice.call(slideContainer.children);
    }
private
setupInfinite: function to setup if infinite is set

@param  {array} slideArray
@return {array} array of updated slideContainer elements