Motivation for this change

Packaging more FOSS chiptune tracker, see #81815.

Last proper releases are blocked by the lack of GDC in nixpkgs (usage of legacy D syntax that ldc and dmd refuse to accept). Fortunately, master actually compiles under non-GDC compilers, though the alternative stereo version that the releases are exposing via tags is lacking behind in commits.

If the stereo version is desired as well, I can look into that though.

I patched out references to a function that uses Dlang's __DATE__, which would display the date of the build in the top-left corner of the application (i.e., "Mar 15 2020"). My thought behind that was to reduce differences between rebuilds without version updates, though I can drop the patch if you think it's not that big of a deal.

Also packaged the ACME Cross-Assembler, as it's a build-time dependency of the tool that assembles the module data into a C64 file. I haven't extensively tested it, but the assembler itself works fine in CheeseCutter's Makefile, and an assembled SID file sounds okay as well.

cc @fgaz

Things done

• Tested using sandboxing (nix.useSandbox on NixOS, or option sandbox in nix.conf on non-NixOS linux)
• Built on platform(s)
  • NixOS
  • macOS
  • other Linux distributions
• Tested via one or more NixOS test(s) if existing and applicable for the change (look inside nixos/tests)
• Tested compilation of all pkgs that depend on this change using nix-shell -p nixpkgs-review --run "nixpkgs-review wip"
• Tested execution of all binary files (usually in ./result/bin/)
• Determined the impact on package closure size (by running nix path-info -S before and after)
• Ensured that relevant documentation is up to date
• Fits CONTRIBUTING.md.