public void addKeyFrameRotation(int keyFrameIndex, Quaternion rotation) {
        float animationTime = keyFrameIndex / fps;
        addTimeRotation(animationTime, rotation);
    }
Add a keyframe for the specified rotation at the specified index.

@param keyFrameIndex the keyframe in which full rotation should be
achieved (&ge;0)
@param rotation the local rotation to apply to the target (not null,
non-zero norm, unaffected)
jme3-core/src/main/java/com/jme3/anim/AnimFactory.java