Setup depends

[phadej]

Let's see how it goes with travis

[RyanGlScott]

Why do you need custom-setup for this trick to work?

[ekmett]

This is an attempt towards getting us a proper custom-setup stanza

[bgamari]

For what it's worth development snapshots of the Cabal library will soon infer a Cabal <1.25 setup-depends constraint where one is not explicitly provided. This is merely a temporary measure until the in-tree version number is bumped; when the final Cabal 2.0 is released the implicit constraint will be Cabal <2.0. See haskell/cabal#3939 for details.

[phadej]

This is obsolete