Sets the outline (or border) an object to the given color
| c | Color (in hex or rgb code) |
Example:
shape1: Object = circle(30, 30, 20)
shape1.stroke("#27a7d8")
shape2: Object = circle(50, 50, 30)
shape2.stroke("rgb(255, 154, 0)")
shape1.draw(1, 1000)
shape2.draw(1, 1000)