move localStorage util to localStorage.js,

update main,js to rquire localStroage,
add simple unit tests to localStroage.test.js,
create symlink of testenv.js to source/assets/scripts,
update package.json with proper recursive call

Signed-off-by: Arthur Lu <learthurgo@gmail.com>

source/assets/scripts/localStorage.js

@@ -0,0 +1,21 @@
+module.exports = {getReviewsFromStorage, saveReviewsToStorage};
+
+/**
+ * @returns {Array<Object>} An array of reviews found in localStorage
+ */
+function getReviewsFromStorage() {
+	let result = JSON.parse(localStorage.getItem('reviews'))
+	if (result) {
+		return result;
+	}
+	return new Array(0);
+}
+
+/**
+ * Takes in an array of reviews, converts it to a string, and then
+ * saves that string to 'reviews' in localStorage
+ * @param {Array<Object>} reviews An array of reviews
+ */
+function saveReviewsToStorage(reviews) {
+	localStorage.setItem('reviews', JSON.stringify(reviews));
+}