Changes to ghc(2)

Changes to ghc:
commit 44512e3c855d8fb36ab6580f4f97f842ebcf4c6c
Author: Alexander Berntsen <alexander@plaimi.net>
Date:   Fri Apr 18 21:41:11 2014 +0200

    Add Data.List.sortOn function (re #9004 and #2659)

    `sortOn` sorts a list by comparing the results of a key function applied to each
    element.  `sortOn f` is equivalent to `sortBy . comparing f`, but has the
    performance advantage of only evaluating `f` once for each element in the
    input list.

    Historical note: This was already proposed in 2008 as part of

      http://www.haskell.org/pipermail/libraries/2008-October/010797.html

    It was, however, the recent re-attempt

      http://www.haskell.org/pipermail/libraries/2014-April/022489.html

    that let `sortOn` make it into base at last. Maybe the other functions
    mentioned in #2659 might be worth reconsidering as well.

commit 1bf6c0e482cfe4b9dfa0b5ed18a5741ba44fc226
Author: Alexander Berntsen <alexander@plaimi.net>
Date:   Thu Apr 17 21:43:35 2014 +0200

    Add reverse application operator Data.Function.(&)

    Add `&` as the reverse application operator with `infixl 1`, which allows
    it to be nested in `$` (re #9008).

    Approved by the core libraries committee on 2013-10-14.

    This also bumps the `base` version number to 4.7.1.0