Cannot find constantize_by anywhere?  analog_clock seemed to hit this so I changed to constantize
Change PlatformImpl startup from being part of launch to be called immediately after bootstrap/loading of jrubyfxrt.  In Java 8, not doing this causes anything dependent on FX toolkit from not properly loading...like any Control
De-couple JRubyFX-FXMLoader from being a runtime depedency.  To use FXMLLoader you must require it to have controller know it should also support FXML.  This also allows Java 8 to load JRubyFX for non-FXML support.  FXMLLoader is current broken for newer Java 8 builds due to removed com.sun packages.