// http://stackoverflow.com/a/10196772/173630
function allKeysToLowerCase(obj) {
    var output = {};
    for (i in obj) {
        if (Object.prototype.toString.apply(obj[i]) === '[object Object]'
            || Object.prototype.toString.apply(obj[i]) === '[object Array]'
        ) {
            output[i.toLowerCase()] = allKeysToLowerCase(obj[i]);
        } else {
            output[i.toLowerCase()] = obj[i];
        }
    }
    return output;
}