Consider allowing for transitivity of dependenies

[hseeberger]

As a user it would be more convenient to not explicitly give all dependendies when calling after, but only the ones that suffice to build the transitive closure.

Maybe make that configurable via an implicit value?

[propensive]

I will add a phantom implicit to determine how the return type is calculated.

Any thoughts as to which should be the default behavior? My concern about transitive dependencies is the explosion of types upon errors.