export layers

Export single layers in the current font as separate UFO fonts.

RF3 RoboFont 3 code which still works in RoboFont 4. Not updated to the new RoboFont 4 APIs yet.

font name
the family name and style name of the current font
layers
a list of all layers in the current font
export
save the selected layers as UFOs next to the current font
overwrite UFO
overwrite existing UFOs with the same name as the exported layers
open font
open the exported fonts in a new Font Window