ReOrganizing the code

GameIntro.js

@@ -0,0 +1,18 @@
+class GameIntro extends Board {
+    constructor(ctx, key) {
+        super(ctx, key);
+        this.controls = {
+            'Space': ()=>this.next(1)
+        }
+    }
+    update() {
+        this.centerText('BreakOut', this.y, '48px', 'Consolas', 'Black');
+        this.centerText('JDG', this.y + 50, '24px', 'Consolas', 'Black');
+    }
+    centerText(txt, y, s, f, c) {
+        this.ctx.font = s + ' ' + f;
+        this.ctx.fillStyle = 'Black';
+        let x = (this.ctx.canvas.width - this.ctx.measureText(txt).width) / 2;
+        this.ctx.fillText(txt, x, y);
+    }
+}