Merge pull request #888 from aristidb/master

haskell: export callPackage to be able to create packages outside haskell-packages.nix
uncrustify: new package

Uncrustify is a source code beautifier for C, C++, C#, ObjectiveC, D,
Java, Pawn and VALA.

Homepage: http://uncrustify.sourceforge.net/
firefox: upgrade to 23.0.1
linux-3.10: upgrade to 3.10.10
add travis ruby gem