var old_list = document.getElementsByClassName('lang');
var new_list = [], old_list_content, i;
for(i = 0; i < old_list.length; i++) {
    old_list_content = old_list[i].innerText;
    new_list.push(old_list_content);
}
console.log(new_list.sort());
for(i = 0; i < old_list.length; i++) {
    old_list[i].innerText = new_list[i];
}