Constraining the Car to the Track - 6

Still not finished with the constraining of the car to the track. I have continued with the geometry stuff and sure hope I slowly have all the necessary functions in the program. I am using my raytracer as a reference for those functions, as I am rather confident that they are correct. Today I added a class for line segments (bounded lines) and added the function to get the closest point on a line to a given point. The general case is implemented, the specializations for the ray and the line segment still need to be done.