I've fixed the faulty Chewbacca fall animation

The falling part of this animation (4182) is faulty with a missing heads layer
in frame 30:
http://www.mediafire.com/view/c2r6bf5ld4pu9x4/Chewbacca_buggy_death_anim_fix.mp4

So this fix lets the first 21 standing transformation frames be played
and then changes the animation to the standard male fall animation by
using it as an extra east animation.