fix: multiple polygons to support holes

[mvarendorff]

This PR fixes a bug with paths that contained multiple polygons which is easiest displayed with an example. Consider the following SVG:

<?xml version="1.0" encoding="utf-8" standalone="no" ?>
<svg viewBox="0 0 240 200" height="180" width="220" version="1.1" xmlns="http://www.w3.org/2000/svg">
<g fill="blue" fill-rule="evenodd">
    <path d="M20 20 h200 v160 h-200 Z M80 40 v100 l100 -50z" />
</g>
</svg>

This SVG currently only creates a single Polygon:

This PR fixes this by keeping track of the current polygon and adding to it in case multiple Z commands are found in the current path. With this change, the demo correctly displays a cut-out:

Notes

• Husky regenerated hooks to point to a blob on my fork, I am not sure how to remedy that but I suppose it's gonna be rebuilt anyway after merge? If I have to fix that in some shape or form, let me know!
• This project is awesome and saved us a lot of time. Thanks a bunch for your effort to create this!

[mvarendorff]

Let me know if you are interested in including this change into the repo; we are using my master branch now internally, so this PR will start to include more stuff that's going to be unrelated to this bugfix :')