This library contains just a single type called Done. It is beneficial to use this type instead of Unit mainly when combined
with Future. First of all it conveys more information than just Future[Unit]. But more importantly it prevents certain class
of bugs caused by automatic conversion of any value to Unit which can when combined with futures lead to quit/hidden throw away
of some value.
This library is inspired by the same type provided by Akka. We do not want to depend on Akka in each project so we separated this into a single-purpose library.