Patch supplied by Vladimír Čunát. Thanks. svn path=/nixpkgs/trunk/; revision=26648
I know, that's not the latest version, but Hakyll-3 is rather different from Hakyll-2 and the upgrade would require more work. svn path=/nixpkgs/trunk/; revision=26291
svn path=/nixpkgs/trunk/; revision=23742
svn path=/nixpkgs/trunk/; revision=22683