added some decorations to EmptyRing so that the rotation is visible;

Rings should have the following methods:
rotate - rotates the ring to a given angle;
rescale - scales the ring according to the new radius value and calls rotate()
translate - called upon player interaction - redrawing the tunnel in a different perspective
draw, collisionCheck - self-explanatory.

added draw method to Line;
Ring now handles rotation logic - rotation, scaling(changes in radius) and translation(changes in center position) logic should be handled by Ring and delegated down to the type object;