convert label to icon

label2image.swift

public extension NSView {
	var image: NSImage? {
		guard let bitmapImageRep = bitmapImageRepForCachingDisplay(in: bounds) else { return nil }
		cacheDisplay(in: bounds, to: bitmapImageRep)
		guard let cgImage = bitmapImageRep.cgImage else { return nil }
		return NSImage(cgImage: cgImage, size: bounds.size)
	}
}