Changes to ghc

Changes to ghc:
commit 3fb19a913f7bf79bd7895c85c750b98308ddb1cf
Author: Edward Z. Yang <ezyang@mit.edu>
Date:   Mon Oct 21 12:59:35 2013 -0700

    s/excpetions/exceptions/

    Signed-off-by: Edward Z. Yang <ezyang@mit.edu>