Make file chooser configurable using FXML tags.

[Oliver-Loeffler]

With having the FileChooser copatible with SceneBuilder, it is desirable to have the file chooser configurable via SceneBuilder.

• start location where to look for files
• custom locations with name per location and actual path
• available path filters (file name condition and description)
• skin

Consider using CSS for skin definition over FXML.