[GREENFOOT-633] Convert export dialog to JavaFX
This currently lives in greenfoot.gui.export (move to .guifx. as you convert). Of all the GUI items being converted, I feel this one probably has some scope for improvement, but see what you think. All the Swing invokeLaters in Exporter will need to become Platform.runLater, but I think otherwise the threading is actually straightforward. Also convert use of GProject to Project.
The properties file code involved in the export will need to be adjusted but I may do that as part of my imminent fix to properties (should be finished 8/12/17 or so).
We may not want to convert the "Export to web page" given that it uses applets. Perhaps something to discuss once someone starts on this.
- Issue type: Task
- Priority: Medium