GridCraft v0.3.0

What's Changed

• About: contributor and model credits compiled in (grab bag + table, self-submitted names) by @echelon in #2
• Release: Flatpak x86_64/aarch64, AppImage zsync updates, README Downloads by @echelon in #14
• README Downloads: where to get it, then builds (Windows first) by @echelon in #15

Full Changelog: v0.1.0...v0.3.0