title: Continue animation from where it was interupted - Core animation
body: <p>I need a a little help with my animation.
  I got two buttons, the first button calls an animation and the second one calls another animation. </p>
  
  <p>Now when I press the first button a code like this one down below will be called. 
  The Problem is that when I press the second button the animation kinda teleports to it's starting position (second animations position), is there a way to make the animations flow together from where it was interupted?</p>
  
  <pre><code>CABasicAnimation *anim1 = [CABasicAnimation animationWithKeyPath:@"transform.rotation"];
  anim1.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut];
  anim1.fromValue = [NSNumber numberWithFloat:((-10*M_PI)/180)];
  anim1.toValue = [NSNumber numberWithFloat:((10*M_PI)/180)];
  anim1.repeatCount = HUGE_VALF;
  anim1.autoreverses = YES;
  anim1.duration = .5;
  [head addAnimation:anim1 forKey:@"transform"];  
  </code></pre>
  
  <p>Virtual picture:</p>
  
  <p><a href="http://i47.tinypic.com/2yopif6.jpg" rel="nofollow">http://i47.tinypic.com/2yopif6.jpg</a></p>
  
  <p>The black line is the first animation, the red is the second animation, and the green is the one I'm trying to figure out. According to the picture it was interupted in the middle of the black. </p>