v0.12.0.0

 -  0.12.0.0 (2020-10-02)
     *  Use ghc-lib-parser rather than haskell-src-exts

        This patch swaps out the parsing library from `haskell-src-exts` to
        `ghc-lib-parser`, which gives us better compatibility with GHC.

        Because almost every module heavily used the Haskell AST provided by
        `haskell-src-exts`, this was a huge effort and it would not have been
        possible without Felix Mulder doing an initial port, GSoC student
        Beatrice Vergani porting several other steps, and Łukasz Gołębiewski and
        Paweł Szulc who helped me finish up things in the home stretch.

        I've generally tried to keep styling 100% compatible with what was there
        before, but some issues may have unintentionally slipped in so please
        report those.

        This introduces one new import styling contributed by Felix: when
        wrapping import lists over multiple lines, you can repeat the module
        name, e.g.:

            import Control.Monad.Except as X (ExceptT (..), MonadError (..))
            import Control.Monad.Except as X (runExceptT, withExceptT)

        This is activated by using `import_align: repeat`.

        Secondly, a new Step was added, `module_header`, which formats the
        export list of a module, including the trailing `where` clause.  Details
        for this new step can be found in the `data/stylish-haskell.yaml`.

     *   Remove `semigroup` dependency for GHC >= 8.0
     *   Bump `strict` upper bound to 0.4
     *   Bump `Cabal` upper bound to 3.3 for test suite