SVG to vello graphics integration

[nixon-voxell]

Goal

Provide a better support for rendering SVGs.

Proposed Solution

This support should come in 2 forms, support for loading SVG files as well as loading SVG from literal strings.

Example SVG:

<svg width="300" height="170" xmlns="http://www.w3.org/2000/svg">
  <rect width="150" height="150" x="10" y="10" rx="20" ry="20" style="fill:red;stroke:black;stroke-width:5;opacity:0.5" />
</svg>