I would like to propose some methods and an event for accessing new entity Pose data.

Adding an enum for Pose (0: STANDING, 1: FALL_FLYING, 2: SLEEPING, 3: SWIMMING, 4: SPIN_ATTACK, 5: SNEAKING, 6: DYING) which would then be accessible via Entity#getPose, and Entity#setPose.

Would also like to see an EntityChangePoseEvent which would fire whenever an entity changes pose, exposing EntityChangePoseEvent#getPose, EntityChangePostEvent#setPose, and possibly allow cancelling if possible.