To write a program which makes different shapes. There is a button that reduces the largest circle by 5px.
Requirements:
1)	With leftmouse click either a circle or rectangle. The probability of circle is 0.8, probability of rectangle is 0.2. For both shapes, the lengths are random(radius for circle or lengths of sides for rectangle) numbers between 10 to 100 (including).
2)	There is a button which calls out Util.getBiggestCircle(main.getChildren()) – this means that shapes must be placed inside main.
3)	When you get Circle object after pressing the button, then the radius of this shape must be reduced by 5px.
4)	When reducing the size of a shape you need to use some kind of animation(for example reduces slowly during 0.5sec)
When pressing the button multiple times all the circles should eventually disappear(radius=0).