Gravity changes, item physics and arrow physic changes.
 Gravity changes
 A new option has been added to orbit, allowing for more realistic gravity which preserves velocity. 
 Gravity will now affect animals and mobs.
 Item physics
 Gravity now affects items, causing them to float when dropped. Crouching will throw the items and make them travel faster.
 Projectile physic changes
 Projectiles (EG: Arrows, snowballs, potions) will now travel at a slower pace and not be affected by gravity.
 Errors fixed with fuel cell system.