Support for <rect>

[rdmurphy]

Hey Rich!

I may just be totally overlooking it but is there currently a way to do something ala SvgRect in the same vein as the other SVG utilities? My Svelte-foo is still pretty basic so perhaps there's a way to tap into Pancake's contexts I've overlooked.

Thanks for sharing the library! I've noticed it appearing all over the place on NYT and it's cool to see how it's being put to use.