working on #62: added ModeLayerRegistry as a central hub to control the modes of all ModeLayers
working on #62:(ModeLayer): removing dev time code, adding toElement to persist, fixing some minor stuff
working on #62: moving Element creating code from the ActiveLayerModel to the CidsLayerFactory
working on #62: eliminating a race condition (sometimes a layer was not displayed correctly, translucency=0) through ensuring that the code is not invokeLater twice
working on #62: minor jalopy changes
working on #62: assure that the translucency is set correctly within the ModeLayer