Fix commit description
Changes to integer-gmp

Changes to integer-gmp:
commit 9744cfbd3465676c801aaef26ca26710997731a4
Author: Herbert Valerio Riedel <hvr@gnu.org>
Date:   Fri Jan 31 18:37:28 2014 +0100

    Improve documentation of `integer-gmp`

    Among other things, this unhides `GHC.Integer` and re-groups the export list.
    Moreover, the internal representation of `Integer` is explained a bit more,
    and `/Since: 0.5.1.0/` annotations have been added.

    Signed-off-by: Herbert Valerio Riedel <hvr@gnu.org>