Keep polyparse 1.4 around because haskell-graphviz depends on the older version.

I've asked upstream to update their cabal file, but until then we'll
need both versions. :-(

svn path=/nixpkgs/trunk/; revision=28021

pkgs/development/libraries/haskell/polyparse/1.4.nix

@@ -0,0 +1,11 @@
+{cabal}:
+
+cabal.mkDerivation (self : {
+  pname = "polyparse";
+  version = "1.4";
+  sha256 = "6e599fb0771e8ce2e1d3a3bbe5eddc2d77b2b4bbb54602f01005dc55dc039d44";
+  meta = {
+    description = "A variety of alternative parser combinator libraries";
+  };
+})
+