3D scenes for [fframes](https://github.com/dmtrKovalenko/fframes): a three.js style scene
graph, glTF and STL models, a CPU rasterizer and a wgpu renderer.
Version 0.0.0 is empty. It reserves the name for the fframes release that adds the crate.
Use the crate through fframes: `fframes = { features = ["3d"] }`, then `fframes::three_d`.