Template for RimWorld Mods in nix

Expects the following VSCode extensions
- ms-dotnettools.vscode-dotnet-runtime
- ms-dotnettools.csharp

Expects the following VSCode settings:
- dotnet.dotnetPath should point at the .NET SDK
- omnisharp.monoPath should point at the mono install dir
- omnisharp.path should point at the omnisharp binary
- dotnet.server.path should point at the omnisharp binary?