Implement Fill([fillRule])

[GimpArm]

It would be nice if the filleRule argument was implemented on the Fill() method.

https://developer.mozilla.org/en-US/docs/Web/API/CanvasRenderingContext2D/fill

Using reflection I was able to invoke the BatchCallAsync() and call fill with the fillRule argument. It worked fine so it should be pretty straight forward to implement it officially.