Changes to ghc(2)

Changes to ghc:
commit eab173b1e4eb588577d105ced57faff2c74cf0b2
Author: Simon Peyton Jones <simonpj@microsoft.com>
Date:   Fri May 16 08:35:25 2014 +0100

    Remove the bit about External Core from flags.xml

    This is a lefover vestige from Austin's removal of External Core

commit 3a61e6de311ad235aec9f0a55201656805e3c04e
Author: Simon Peyton Jones <simonpj@microsoft.com>
Date:   Fri May 16 08:34:44 2014 +0100

    Tighten up wording in the section on let-generalisation and MonoLocalBinds