list-extras-0.4.1.1: Common not-so-common functions for lists

Common not-so-common functions for lists.

Since Data.List.Extras is prime realestate for extensions to Data.List, if you have something you'd like to contribute feel free to contact the maintainer (I'm friendly). I'm amenable to adopting code if you think your functions aren't enough for a package on their own. Or if you would rather maintain a separate package I can share the Data.List.Extras.Foo namespace.