Added game state, allow paddle movement

PongGame/wwwroot/js/pong.js

@@ -79,6 +79,16 @@ leavelobby.addEventListener("click", function (event) {
   event.preventDefault();
 });
 
+function movePaddle(direction) {
+  connection.invoke("MovePaddle", direction).catch(function (err) {
+    return console.error(err.toString());
+  });
+}
+
+function moveUp() { return movePaddle(-1); }
+function stopPaddle() { return movePaddle(0); }
+function moveDown() { return movePaddle(1); }
+
 connection.start().then(function () {
   console.info(`Connected!`);
   connectionStatus.textContent = "Connected!";