No Z-Fighting

Fixed map item frame z-fighting with map (from a far distance, mostly noticeable on large walls of maps)
Fixed drowned head and torso and legs
Fixed pixels appearing by reins of horse in first person (not really z-fighting but produces similar effect so I added it)
Fixed horse reins
Fixed horse ears and head
Tweaked pig model to fix other issue with legs and torso
Fixed spider and cave spider leg
Fixed top (with block placed on top) and bottom of wall post
Fixed skeleton leg and torso

Chicken changed from texture to model
Shulker box model removed as it's unneeded