feat(server): seperate server part and ability to run server without electron

src/background/shuffle.js

@@ -2,7 +2,7 @@
  * Shuffles array in place.
  * @param {Array} a items An array containing the items.
  */
-export default function shuffle(a) {
+module.exports = function shuffle(a) {
     let j, x, i;
     for (i = a.length - 1; i > 0; i--) {
         j = Math.floor(Math.random() * (i + 1));