CustomEvent = function (event, params) {
        params = params || {
            bubbles: false,
            cancelable: false,
            detail: undefined
        };
        var evt = document.createEvent('CustomEvent');
        evt.initCustomEvent(event, params.bubbles, params.cancelable, params.detail);
        return evt;
    }
CustomEvent constructor polyfill for IE
@return {[type]} [description]