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`.
The base that comes with ghc-7.6.1 no longer includes Prelude.catch;
so these modules were changed so that there is no warning for
import Prelude hiding (catch)
At the same time these changes should be compatible with older GHCs,
since the catch being has never been the one in the Prelude.
This fixes a "Prelude.head" exception observed with windows that have no title.
Reproduce by placing several windows in the tabbed layout, then starting
'xterm -name ""'. Thanks to Andrea for pointing out the issue.
