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 patch changes SpawnOn, DynamicHooks and UrgencyHooks to
use X.U.ExtensibleState instead of IORefs. This simplifies the
usage of those modules thus also breaking current configs.
Allows runtime creation and modification of ManageHooks. Also allows one-shot
ManageHooks that are removed after the fire. Note that if several transient
hooks fire at once, only the most recently defined is executed, and all
are removed.
