end attribute for animation
width and height of a rectangle is enlarged, x is moved to the right
in 30s.
The animation can be stopped with the event
mouseout of the rectangle.
mouseout occurs according to the specification,
if the mouse is moved away from the element.
It is not mentioned, that the conditions is fulfilled,
if the element moves away from the mouse, therefore
the mouse has to be moved, not just the element.
end with mouseout