fixed sprite to normal ones that CodingTrain#23 made

Author: DaGuT

sketch.js

@@ -14,8 +14,8 @@ var bgImg;
 var bgX = 0;
 
 function preload() {
-  pipeBodySprite = loadImage("./graphics/pipe_body.png");
-  pipePeakSprite = loadImage("./graphics/pipe_body.png");
+  pipeBodySprite = loadImage("./graphics/horn_body_filled.png");
+  pipePeakSprite = loadImage("./graphics/horn_tip_filled.png");
   birdSprite = loadImage("graphics/train.png");
   bgImg = loadImage("graphics/background.png");
 }