Don't write Setup.hs file during cabal init.

[m-renaud]

When build-type: Simple the contents of Setup.hs MUST BE standard. It is only
in advanced cases where a custom setup file is needed.

This also has the positive consequence of simplifying the directory contents created during package initialization.

---

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• Patches conform to the coding conventions.
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[DanielG]

Could you explain what exactly you're trying to accomplish here?

While Setup.hs isn't technically required to build a package with cabal some distributions such as Debian still use it to build haskell packages directly from tarballs, without exe:cabal involved.

[phadej]

@DanielG they could (and should) use standard Setup.hs. There are packages on Hackage which don't have Setup.hs inside them.

[DanielG]

Huh, I'd assumed we're enforcing Setup.hs existing in hackage-serever. Well nevermind then.

[m-renaud]

Any other concerns or should I go ahead and merge this in? CI is all green.

[phadej]

@m-renaud go ahead.