Add to stackage

[flip111]

Hello, this library looks really good to me and i would like to use it in my haskell stack project. Could it be added to stackage ?

[muesli4]

Hello, I looked into this and it seems data-default-instances-base, which is a dependency, is also not on stackage.

Edit: It looks like you already took care of that mauke/data-default#22 ;)

[flip111]

the dependency is on stackage now