flipPrev() does not work when disableFlipByClick is true

[WilliamIsted]

When disableByFlipClick is true, flipNext() does not function. This appears to be a similar issue to #18.

StPageFlip/src/Flip/Flip.ts

Lines 255 to 260 in ab30ecc

	public flipPrev(corner: FlipCorner): void {
	this.flip({
	x: 10,
	y: corner === FlipCorner.TOP ? 1 : this.render.getRect().height - 2,
	});
	}

This is resolved by replacing line 257 with x: this.render.getRect().left + 10,.