Update submodules: plugins (new commits)

plugins:
    c941fb8 Chris Smith <chris@dmdirc.com>
            Create the lag display panel before adding it.

            It works better this way.

            Fixes-Issue: CLIENT-441
            Gerrit: http://gerrit.dmdirc.com/3155

Change-Id: I4e74b5cbf7c25ca404c044582f783c26e08e96cf