Ability to Specify Sharp Constructor Options

[emmercm]

I have an issue similar to lovell/sharp#729 where SVGs get rasterized at load and then scaling them up with the resize method greatly reduces quality.

The suggestion in that issue is to specify a high density in the constructor (docs: https://sharp.pixelplumbing.com/api-constructor), but it looks like passing the options parameter isn't supported right now:

metalsmith-sharp/src/index.js

Line 27 in 9c57422

const sharp = Sharp(image.contents)

Hoping that can get added as option to the in some way, at the same level as say src or methods, and maybe the value could either be an object or a function that returns an object, similar to args.

Thanks!