This is a convenience module in order to have less import noise. It
re-exports the following:
a) Commonly used modules in full (Data.Foldable, Data.Applicative, and
so on); though only those that play nicely with each other, so that
XMonad.Prelude can be imported unqualified without any problems.
This prevents things like `Prelude.(.)` and `Control.Category.(.)`
fighting with each other.
b) Helper functions that don't necessarily fit in any other module;
e.g., the often used abbreviation `fi = fromIntegral`.
This should not cause any working configs to stop working, because IO is an instance of MonadIO, and because complete configs will pin down the type of the call to IO. Note that XMonad.Config.Arossato is not a complete config, and so it needed some tweaks; with a main function, this should not be a problem.
