Major Haskell packages overhaul.

Several changes, some highlights:

  * Structure of haskell-packages.nix updated. It's now easier to
    select different default versions of packages for different
    versions of GHC.

  * GHC 7.0.2 is now default.

  * Haskell Platform 2011.2.0.0 has been added and is now default.

  * Several packages have been updated
    (gtk2hs, gitit, xmonad, darcs, ...).

  * Some old packages have been removed.

svn path=/nixpkgs/trunk/; revision=26288

pkgs/development/libraries/haskell/regex-base/0.93.2.nix

@@ -2,8 +2,8 @@
 
 cabal.mkDerivation (self : {
   pname = "regex-base";
-  version = "0.93.2"; # Haskell Platform 2010.2.0.0
-  sha256 = "20dc5713a16f3d5e2e6d056b4beb9cfdc4368cd09fd56f47414c847705243278";
+  version = "0.93.2"; # Haskell Platform 2010.2.0.0, 2011.2.0.0
+  sha256 = "0y1j4h2pg12c853nzmczs263di7xkkmlnsq5dlp5wgbgl49mgp10";
   propagatedBuildInputs = [mtl];
   meta = {
     description = "Replaces/Ehances Text.Regex";