Update submodules: util (new commits)

util:
    76ba1d7 Chris Smith <chris@dmdirc.com>
            Add FileUtils.

            Not tested or used yet :)

            Gerrit: http://gerrit.dmdirc.com/4042

Change-Id: I43f0d9f2bd3d1519084b159b5ff96c0aba1a62cf