Fix up CoreAliasDialogModel

Change-Id: I20df1c9c0b1db6ceece276a96382196ed13cedd8
Depends-On: d1f48e58e8883d4db974509bdf00db5d6edf3eb6
Reviewed-on: http://gerrit.dmdirc.com/3621
Automatic-Compile: DMDirc Build Manager
Reviewed-by: Chris Smith <chris@dmdirc.com>
Update submodules: plugins (new commits)

plugins:
    2482d2a Greg Holmes <greg@dmdirc.com>
            Use new loadModel method in AliasDialogModel.

            Depends-On: 17cdb63df9dde46a0a4a4761e03ffb24ae8bac55
            Gerrit: http://gerrit.dmdirc.com/3622

Change-Id: I7e0b60ed3ef4cb76af5b56c6b8da0d5970e5881e