haskell-platform: install binaries and libraries into the user environment

Fixes https://github.com/NixOS/nixpkgs/issues/2968.
haskell-ariadne: update to version 0.1.2.3
haskell-language-c: update to version 0.4.7
haskell-rethinkdb: update to version 1.15.2.0
haskell-vty-ui: update to version 1.8