* remove extenders (never panned out, used by exactly two components that we can find .. anywhere)
* move animations to libplasmagqv
* schedule js anims to be put into the js scriptengine
* move all QGraphicsProxyWidgets, except for IconWidget which is still used by PopupApplet, into libplasmaqgv
* create a subclass-able private class for Applet
TODO: move out icon widget, address FIXMES in graphicswidgetappletprivate.cpp and decide how to register the "right" private class for instantiation in Applet ctors
