Inject StatusBarManager, instead of singletonning.

Change-Id: If4bf7c53ade24b6cc3b637aa9ac92410a0b64889
Reviewed-on: http://gerrit.dmdirc.com/2926
Automatic-Compile: DMDirc Build Manager
Reviewed-by: Greg Holmes <greg@dmdirc.com>
Update submodules: plugins (new commits)

plugins:
    64af5c5 Chris Smith <chris@dmdirc.com>
            Inject StatusBarManager, instead of singletonning.

            Gerrit: http://gerrit.dmdirc.com/2927

Change-Id: I65f83bbaaebbd13738d4f12d82f97233676b9a8f