title: SpriteKit animateWithTextures in iOS7 not working
body: <p>I'm trying to add a little animation based on two pngs, where I create two SKTextures with two images and create an SKAction, and have it run forever with [SKAction repeatActionForever] but nothing is happening, nothing is appearing on the screen.</p>
  
  <p>Here's my code:</p>
  
  <pre><code>_planePropeller = [SKSpriteNode spriteNodeWithImageNamed:@"PLANE PROPELLER 1.png"];
          _planePropeller.xScale = 0.2;
          _planePropeller.yScale = 0.2;
          _planePropeller.position = CGPointMake(screenWidth/2, _plane.size.height+10);
          SKTexture *propeller1 = [SKTexture textureWithImageNamed:@"PLANE PROPELLER 1.png"];
          SKTexture *propeller2 = [SKTexture textureWithImageNamed:@"PLANE PROPELLER 2.png"];
          SKAction *spin = [SKAction animateWithTextures:@[propeller1, propeller2] timePerFrame:0.1];
          SKAction *spinForever = [SKAction repeatActionForever:spin];
          [_planePropeller runAction:spinForever];
          [self addChild:_planePropeller];
  </code></pre>
  
  <p>Any ideas? Thanks a lot in advance!</p>