Notably also adds some metadata files for NixOS
* add support for linux clang cross compiles
* add linux clang instructions
* un-capitalize Mob.horse.*
* update the description in flake.nix
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Co-authored-by: Loki <lokirautio@gmail.com>
1. Converted `MinecraftWindows.rc` and `Resource.h` to UTF-8 from UTF-16(they didn't use any UTF-16 symbols anyway);
2. Added explicit signed->unsigned integer casts in `gdraw_d3d1x_shared.inl` for C++11 compatibility
3. Linked against `legacy_stdio_definitions.lib` to avoid undefined references to `_vsnprintf` llvm-link errors