Added persistence of game state to localstorage after each move

Added rebuilding of game state from localstoage on page load
Added New Game button to allow game restarts now that refreshes resume the game

js/game_manager.js

@@ -1,7 +1,7 @@
-function GameManager(size, InputManager, Actuator, ScoreManager) {
+function GameManager(size, InputManager, Actuator, StorageManager) {
   this.size         = size; // Size of the grid
   this.inputManager = new InputManager;
-  this.scoreManager = new ScoreManager;
+  this.storageManager = new StorageManager;
   this.actuator     = new Actuator;
 
   this.startTiles   = 2;
@@ -15,6 +15,7 @@ function GameManager(size, InputManager, Actuator, ScoreManager) {
 
 // Restart the game
 GameManager.prototype.restart = function () {
+  this.storageManager.clearGameState();
   this.actuator.continue();
   this.setup();
 };
@@ -35,15 +36,24 @@ GameManager.prototype.isGameTerminated = function () {
 
 // Set up the game
 GameManager.prototype.setup = function () {
-  this.grid        = new Grid(this.size);
+  var previousGameState = this.storageManager.getGameState();
 
-  this.score       = 0;
-  this.over        = false;
-  this.won         = false;
-  this.keepPlaying = false;
+  if (previousGameState) {
+      this.grid        = new Grid(previousGameState.grid.size, previousGameState.grid.cells);
+      this.score       = previousGameState.score;
+      this.over        = previousGameState.over;
+      this.won         = previousGameState.won;
+      this.keepPlaying = previousGameState.keepPlaying;
+  } else {
+      this.grid        = new Grid(this.size);
+      this.score       = 0;
+      this.over        = false;
+      this.won         = false;
+      this.keepPlaying = false;
 
-  // Add the initial tiles
-  this.addStartTiles();
+      // Add the initial tiles
+      this.addStartTiles();
+  }
 
   // Update the actuator
   this.actuate();
@@ -68,20 +78,33 @@ GameManager.prototype.addRandomTile = function () {
 
 // Sends the updated grid to the actuator
 GameManager.prototype.actuate = function () {
-  if (this.scoreManager.get() < this.score) {
-    this.scoreManager.set(this.score);
+  if (this.storageManager.getBestScore() < this.score) {
+    this.storageManager.setBestScore(this.score);
   }
 
+  this.storageManager.setGameState(this.serializeGameState());
+
   this.actuator.actuate(this.grid, {
     score:      this.score,
     over:       this.over,
     won:        this.won,
-    bestScore:  this.scoreManager.get(),
+    bestScore:  this.storageManager.getBestScore(),
     terminated: this.isGameTerminated()
   });
 
 };
 
+GameManager.prototype.serializeGameState = function () {
+    return {
+        size:        this.size,
+        grid:        this.grid.gridState(),
+        score:       this.score,
+        over:        this.over,
+        won:         this.won,
+        keepPlaying: this.keepPlaying
+    };
+}
+
 // Save all tile positions and remove merger info
 GameManager.prototype.prepareTiles = function () {
   this.grid.eachCell(function (x, y, tile) {