Small test app for various rust9x functionality

1. Install just (cargo install just).
2. Update the lib paths in .cargo/config.toml to match yours. If you want to build for a system that is already supported natively by your default msvc installation, you can remove these or comment them out.
3. Update the variables in the justfile. The rust9x toolchain name and editbin.exe path (from your modern msvc build tools) in particular are important.
4. Use just build --release to build using the rust9x toolchain, and regular cargo for normal toolchain builds.

• Make sure to put hh3gf.golden.exe next to the executable for testing.
• If you plan on testing on Windows 9x/ME, make sure to place unicows.dll next to the executable
• If you link dynamically, make sure to provide the necessary runtime libraries.

Credits

hh3gf.golden.exe is taken from https://github.com/pts/pts-tinype to test stdout redirection.