Builds have been fixed. I won't rewrite .travis.yml to Stack right now because
I think that people still use Cabal for installing libraries more often than they use Stack, and thus testing under Cabal is more important than testing under Stack.
Once fmt is added to Stackage, we'll get Stackage testing for free.
Consider rewriting
.travis.yml
to usestack
instead how it's done here: https://github.com/serokell/universum/blob/master/.travis.ymlNow builds are failing: https://travis-ci.org/aelve/fmt/jobs/218088641