Collision Fixes

So I added collision, and then I was trying to add a tractor beam. Collisions, you got circles, you find the collision normal or the angle between, and you compare the mass and the velocity, and you exchange the energy like pool balls. Originally I was thinking the tractor beam  should just apply force to the targeted object, but then, I had this clever idea. "Every action has an equal and opposite reaction." Nobody ever thought that before. So I thought hey the tractor beam should apply the same force, pull and push to both the ship and the target. Then I realized that I could reuse the collision math with a negative force to pull objects together!