SVG deserialization support

[themkat]

Information

My attempt at supporting SVG loading as part of the resource pipeline. Works with both desktop/native build and wasm. Needs only the resvg crate to do so.

Read in the linked issue in #4 that users wanted SVGs automatically rendered to a texture. That is what I have tried (and in my view succeeded) to accomplish here 🙂

The code in Deserialize for Texture2D might be refactored, but found no prettier way to do it right now.

Fixes #4

Testing

Simply modified the logo example in three-d to only show the colors of the image. (that examples fragment shader does some minor processing I did not look into, but simply removed when testing).

Loaded the following image from wikimedia for testing wasm build, as it doesn't seem like the local resources were included.
https://upload.wikimedia.org/wikipedia/commons/5/54/Bot%C3%B3n_Me_gusta.svg

wasm:

native on Mac OS X (with the test.svg image included here):

Image is probably stretched a tiny bit in both cases, but mostly so on the native version.

[asny]

Super nice, only very minor comments. Thanks for the contribution 🙏