Add horizontal card to printing.

[boxthor]

I have a Cricut, and using their print registration marks requires a 14mm margin on all sides, which makes a 3x3 grid just not fit 8.5x11 paper. Having a 2x2 grid wastes a lot of paper material, but I think there'd be enough room to add a horizontal card beneath the 2x2 grid.

[boxthor]

Disregard, just turned it landscape, lol

[luziferius]

cut marks for silhouette cutters do not yet work correctly. When I implemented the marks I didn't realize it needed additional support files. And MTGProxyPrinter can't generate them yet

I'll add an in-app note about that in the next Bugfix release