Replace cookiecutter with Stack template?

[sir4ur0n]

Currently Funflow provides a Cookiecutter template, which - I think - is not a widespread tool in the Haskell ecosystem.

Stack provides a templating feature out of the box so I think it would make more sense to provide this instead (or in addition to Cookiecutter?), so that anyone could do e.g.

stack new my-first-funflow-project https://raw.githubusercontent.com/tweag/funflow/master/stack-template