Merge pull request #328 from serras/master

Revert way to report errors when deferred as warnings
Remove `withErrorHandler`, use `liftExceptions` instead
Merge pull request #329 from DanielG/dev-error

Remove `withErrorHandler`, use `liftExceptions` instead
Remove dedicated exception handling in `check` completely

Exceptions are already caught at the top level so this is unnecessary.
Merge pull request #330 from DanielG/dev-error

Remove dedicated exception handling in `check` completely
Fix UtilSpec
Add myself to `Author` in ghc-mod.cabal
error messages are stored after NG, not printed in stderr.
fixing typos.
Adde myself to Authors in cabal file