Generalize call to take a `Closure (SerializableDict a)`

[davidsd]

Currently the type of Control.Distributed.Process.call is

call :: Serializable a
     => Static (SerializableDict a)
     -> NodeId
     -> Closure (Process a)
     -> Process a

However, it can be straightforwardly generalized to take a Closure (SerializableDict a) instead of a Static (SerializableDict a). This is strictly more general because a Static a can always be turned into a Closure a, but not vice-versa. The necessary code, along with a description of a use case for the more general call is here.

I suggest providing a more general callClosure that takes a Closure (SerializableDict a) and re-defining call in terms of it.

I volunteer to implement.