changes

we removed the wheel we had put in the middle for support as we have weighted down the back with the nxt box, we replaced it withe the light sensor that has side sheilds to stop it being interfered with. we also decided that the free turning back would cause a problem so we made it connect to the main front and stoped it from freely turning, we built a frame on the front so we can add some kind of pushing wall which will be added soon