Fixed an issue where the merhcant would hang still in the air at a certain distance.
Lowered the distance at which it lands and they will now always land properly regardless of player altitude.

Updated behavior: Merchants should no longer fly on top of you, but wait patiently 500m+ away from you and slowly descend in their place if you stand / move on the ground.

+ the merchant ships now have landing gears on the front, making them easier to land