Changes to ghc

Changes to ghc:
commit 4d70840db82065bf19767a5f7231a9b1a3f56e38
Author: Benno Fünfstück <benno.fuenfstueck@gmail.com>
Date:   Fri Jan 3 17:17:30 2014 +0100

    Fix #5209: Reset GHCi prompt in multiline mode

    GHCi didn't reset the multiline prompt when an exception (in particular,
    the UserInterrupt exception) occured. This commit uses `finally` to
    reset the prompt in all cases.