changes

added improved collision detection
added improved acceleration equation
public double getA (double x_pos) {
    double accln;
    accln = scale2*G*(-m2)/((x_pos-x2)*(x_pos-x2))*(x_pos-x2)/Math.abs(x_pos-x2)+scale1*G*(-m1)/((x_pos-x1)*(x_pos-x1))*(x_pos-x1)/Math.abs(x_pos-x1);
    return accln;
   
}