Add ability for `require-bin` to be false

[ericcornelissen]

Instead of requiring a project to have a bin, I want to require that my project does not have a bin. The options "error", "warning", and "off" don't cover this use case. Looking to ESLint for inspirations (which seems to be what this project's configuration language is based on), some configuration like the following could work:

{
  "require-bin": ["error", "always"] // (default) enforce having a bin
}

{
  "require-bin": ["error", "never"] // having no bin
}