Update submodules: plugins (new commits)

plugins:
    def4aca Chris Smith <chris@dmdirc.com>
            Use new formatter method.

            Gerrit: http://gerrit.dmdirc.com/3987

Change-Id: Ib21f388a826ce6105ffeac73f0b400f71807cbad
Update submodules: util (new commits)

util:
    2488740 Chris Smith <chris@dmdirc.com>
            Specific versions.

            Gerrit: http://gerrit.dmdirc.com/4005

Change-Id: I4fcf77de9d9bf56ef85ceb0bde1fd33f1fc181c1