Merge pull request #306 from DanielG/dev

Don't fall back to sandbox if cabal file fails to parse
adding CodingStyle.
adding a test for foreign export.
removing warnings.
Move GhcModError to Types.hs
Make GhcModT's MonadState instance pass through

..to the underlying monad
Make `parseCabalFile` use MonadError
Generate cabal.sandbox.config in test/data/broken-cabal
Add a test for gmsGet/Put
note