This PR adds new `ex.Debug` static for more convenient debug drawing where you might not have a graphics context accessible to you. This works by batching up all the debug draw requests and flushing them during the debug draw step.
* `ex.Debug.drawRay(ray: Ray, options?: { distance?: number, color?: Color })`
* `ex.Debug.drawBounds(boundingBox: BoundingBox, options?: { color?: Color })`
* `ex.Debug.drawCircle(center: Vector, radius: number, options?: ...)`
* `ex.Debug.drawPolygon(points: Vector[], options?: { color?: Color })`
* `ex.Debug.drawText(text: string, pos: Vector)`
* `ex.Debug.drawLine(start: Vector, end: Vector, options?: LineGraphicsOptions)`
* `ex.Debug.drawLines(points: Vector[], options?: LineGraphicsOptions)`
* `drawPoint(point: Vector, options?: PointGraphicsOptions)`