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`.
1. Added 'additionalNav2DKeys' which adds keybindings for the cartesian product
of direction keys and (modifier, action) pairs given.
2. Added 'navigation2D' which combines that with 'withNavigation2DConfig'.
3. Added 'additionalNav2DKeysP' and 'navigation2DP' which do the same, but use
the 'additionalKeysP' syntax.
This is a new module to support directional navigation across multiple screens.
As such it is related to X.A.WindowNavigation and X.L.WindowNavigation, but it
is more general. For a detailed discussion of the differences, see
http://www.cs.dal.ca/~nzeh/xmonad/Navigation2D.pdf.
